From a7ed14b7414845398771e26c97a5392b445f33e7 Mon Sep 17 00:00:00 2001
From: alisdair sullivan <alisdairsullivan@yahoo.ca>
Date: Tue, 1 Jun 2010 01:03:28 -0700
Subject: [PATCH] utf8, both varieties of utf16 and both varieties of utf32 are
 now autodetected properly (either via bom or null order) and decoded properly

---
 src/jsx.erl         | 595 +++++++-------------------------------------
 src/jsx_common.hrl  |  83 ++++++
 src/jsx_utf16.erl   | 476 +++++++++++++++++++++++++++++++++++
 src/jsx_utf16le.erl | 476 +++++++++++++++++++++++++++++++++++
 src/jsx_utf32.erl   | 476 +++++++++++++++++++++++++++++++++++
 src/jsx_utf32le.erl | 476 +++++++++++++++++++++++++++++++++++
 src/jsx_utf8.erl    | 476 +++++++++++++++++++++++++++++++++++
 7 files changed, 2547 insertions(+), 511 deletions(-)
 create mode 100644 src/jsx_common.hrl
 create mode 100644 src/jsx_utf16.erl
 create mode 100644 src/jsx_utf16le.erl
 create mode 100644 src/jsx_utf32.erl
 create mode 100644 src/jsx_utf32le.erl
 create mode 100644 src/jsx_utf8.erl

diff --git a/src/jsx.erl b/src/jsx.erl
index 2a76d59..b6a7698 100644
--- a/src/jsx.erl
+++ b/src/jsx.erl
@@ -24,26 +24,42 @@
 -module(jsx).
 -author("alisdairsullivan@yahoo.ca").
 
--export([decoder/0, decoder/1, decoder/2]).
+-export([decoder/0, decoder/1, decoder/2, detect_encoding/4]).
 
 
 decoder() ->
     decoder([]).
 
 decoder(Opts) ->
-    F = fun(end_of_stream, State) -> lists:reverse(State) ;(Event, State) -> [Event] ++ State  end,
+    F = fun(end_of_stream, State) -> lists:reverse(State) ;(Event, State) -> [Event] ++ State end,
     decoder({F, []}, Opts).
 
 decoder({F, _} = Callbacks, OptsList) when is_list(OptsList), is_function(F) ->
-    Opts = parse_opts(OptsList),
-    decoder(Callbacks, Opts);
+    start(Callbacks, OptsList);
 decoder({{Mod, Fun}, State}, OptsList) when is_list(OptsList), is_atom(Mod), is_atom(Fun) ->
-    Opts = parse_opts(OptsList),
-    decoder({fun(E, S) -> Mod:Fun(E, S) end, State}, Opts);
-decoder(Callbacks, Opts) ->
-    fun(Stream) -> try start(Stream, [], Callbacks, Opts) catch error:function_clause -> {error, badjson} ;error:badjson -> {error, badjson} end end.
+    start({fun(E, S) -> Mod:Fun(E, S) end, State}, OptsList).
 
+start(Callbacks, OptsList) ->
+    Opts = parse_opts(OptsList),
+    F = case proplists:get_value(encoding, OptsList, auto) of
+        utf8 -> fun jsx_utf8:start/4
+        ; utf16 -> fun jsx_utf16:start/4
+        ; utf32 -> fun jsx_utf32:start/4
+        ; utf16le -> fun jsx_utf16le:start/4
+        ; utf32le -> fun jsx_utf32le:start/4
+        ; auto -> fun jsx:detect_encoding/4
+    end,
+    start(Callbacks, Opts, F).
     
+start(Callbacks, Opts, F) ->
+    fun(Stream) -> 
+        try F(Stream, [], Callbacks, Opts) 
+        catch 
+            error:function_clause -> {error, badjson} 
+            ; error:badjson -> {error, badjson} 
+        end 
+    end.
+
 parse_opts(Opts) ->
     parse_opts(Opts, {false, codepoint}).
 
@@ -57,511 +73,68 @@ parse_opts([{escaped_unicode, Value}|Rest], {Comments, _EscapedUnicode}) ->
     parse_opts(Rest, {Comments, Value});
 parse_opts([_UnknownOpt|Rest], Opts) ->
     parse_opts(Rest, Opts).
-  
-  
-%% option flags
-
--define(comments_enabled(X), {true, _} = X).
--define(escaped_unicode_to_ascii(X), {_, ascii} = X).
--define(escaped_unicode_to_codepoint(X), {_, codepoint} = X).
-
-%% whitespace
--define(space, 16#20).
--define(tab, 16#09).
--define(cr, 16#0D).
--define(newline, 16#0A).
-
-%% object delimiters
--define(start_object, 16#7B).
--define(end_object, 16#7D).
-
-%% array delimiters
--define(start_array, 16#5B).
--define(end_array, 16#5D).
-
-%% kv seperator
--define(comma, 16#2C).
--define(quote, 16#22).
--define(colon, 16#3A).
-
-%% string escape sequences
--define(escape, 16#5C).
--define(rsolidus, 16#5C).
--define(solidus, 16#2F).
--define(formfeed, 16#0C).
--define(backspace, 16#08).
--define(unicode, 16#75).
-
-%% math
--define(zero, 16#30).
--define(decimalpoint, 16#2E).
--define(negative, 16#2D).
--define(positive, 16#2B).
-
-%% comments
--define(star, 16#2a).
-
--define(is_hex(Symbol),
-    (Symbol >= $a andalso Symbol =< $z); (Symbol >= $A andalso Symbol =< $Z); 
-        (Symbol >= $0 andalso Symbol =< $9)
-).
-
--define(is_nonzero(Symbol),
-    Symbol >= $1 andalso Symbol =< $9
-).
-
--define(is_noncontrol(Symbol),
-    Symbol >= ?space
-).
-
--define(is_whitespace(Symbol),
-    Symbol =:= ?space; Symbol =:= ?tab; Symbol =:= ?cr; Symbol =:= ?newline
-).
     
     
-%% this code is mostly autogenerated and mostly ugly. apologies. for more insight on
-%%   Callbacks or Opts, see the comments accompanying decoder/2 (in jsx.erl). Stack 
-%%   is a stack of flags used to track depth and to keep track of whether we are 
-%%   returning from a value or a key inside objects. all pops, peeks and pushes are 
-%%   inlined. the code that handles naked values and comments is not optimized by the 
-%%   compiler for efficient matching, but you shouldn't be using naked values or comments 
-%%   anyways, they are horrible and contrary to the spec.
+%% first check to see if there's a bom, if not, use the rfc4627 method for determining
+%%   encoding. this function makes some assumptions about the validity of the stream
+%%   which may delay failure later than if an encoding is explicitly provided.    
+    
+%% utf8 bom detection    
+detect_encoding(<<16#ef, 16#bb, 16#bf, Rest/binary>>, Stack, Callbacks, Opts) ->
+    jsx_utf8:start(Rest, Stack, Callbacks, Opts);    
+    
+%% utf32-little bom detection (this has to come before utf16-little)
+detect_encoding(<<16#ff, 16#fe, 0, 0, Rest/binary>>, Stack, Callbacks, Opts) ->
+    jsx_utf32le:start(Rest, Stack, Callbacks, Opts);    
+    
+%% utf16-big bom detection
+detect_encoding(<<16#fe, 16#ff, Rest/binary>>, Stack, Callbacks, Opts) ->
+    jsx_utf16:start(Rest, Stack, Callbacks, Opts);
+    
+%% utf16-little bom detection
+detect_encoding(<<16#ff, 16#fe, Rest/binary>>, Stack, Callbacks, Opts) ->
+    jsx_utf16le:start(Rest, Stack, Callbacks, Opts);
+    
+%% utf32-big bom detection
+detect_encoding(<<0, 0, 16#fe, 16#ff, Rest/binary>>, Stack, Callbacks, Opts) ->
+    jsx_utf32:start(Rest, Stack, Callbacks, Opts);
+    
+%% utf8 null order detection
+detect_encoding(<<X, Y, _Rest/binary>> = JSON, Stack, Callbacks, Opts) when X =/= 0, Y =/= 0 ->
+    jsx_utf8:start(JSON, Stack, Callbacks, Opts);
 
-start(<<S, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) -> 
-    start(Rest, Stack, Callbacks, Opts);
-start(<<?start_object, Rest/binary>>, Stack, Callbacks, Opts) ->
-    object(Rest, [key|Stack], fold(start_object, Callbacks), Opts);
-start(<<?start_array, Rest/binary>>, Stack, Callbacks, Opts) ->
-    array(Rest, [array|Stack], fold(start_array, Callbacks), Opts);
-start(<<?quote, Rest/binary>>, Stack, Callbacks, Opts) ->
-    string(Rest, Stack, Callbacks, Opts, []);
-start(<<$t, Rest/binary>>, Stack, Callbacks, Opts) ->
-    tr(Rest, Stack, Callbacks, Opts);
-start(<<$f, Rest/binary>>, Stack, Callbacks, Opts) ->
-    fa(Rest, Stack, Callbacks, Opts);
-start(<<$n, Rest/binary>>, Stack, Callbacks, Opts) ->
-    nu(Rest, Stack, Callbacks, Opts);
-start(<<?negative, Rest/binary>>, Stack, Callbacks, Opts) ->
-    negative(Rest, Stack, Callbacks, Opts, "-");
-start(<<?zero, Rest/binary>>, Stack, Callbacks, Opts) ->
-    zero(Rest, Stack, Callbacks, Opts, "0");
-start(<<S, Rest/binary>>, Stack, Callbacks, Opts) when ?is_nonzero(S) ->
-    integer(Rest, Stack, Callbacks, Opts, [S]);
-start(<<?solidus, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
-    maybe_comment(Rest, fun(Resume) -> start(Resume, Stack, Callbacks, Opts) end);
-start(<<>>, Stack, Callbacks, Opts) ->
-    {incomplete, fun(Stream) -> start(Stream, Stack, Callbacks, Opts) end}.
+%% utf32-little null order detection
+detect_encoding(<<X, 0, 0, 0, _Rest/binary>> = JSON, Stack, Callbacks, Opts) when X =/= 0 ->
+    jsx_utf32le:start(JSON, Stack, Callbacks, Opts);
+    
+%% utf16-big null order detection
+detect_encoding(<<0, X, 0, Y, _Rest/binary>> = JSON, Stack, Callbacks, Opts) when X =/= 0, Y =/= 0 ->
+    jsx_utf16:start(JSON, Stack, Callbacks, Opts);
+    
+%% utf16-little null order detection
+detect_encoding(<<X, 0, Y, 0, _Rest/binary>> = JSON, Stack, Callbacks, Opts) when X =/= 0, Y =/= 0 ->
+    jsx_utf16le:start(JSON, Stack, Callbacks, Opts);
 
-
-maybe_done(<<S, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) ->
-    maybe_done(Rest, Stack, Callbacks, Opts);
-maybe_done(<<?end_object, Rest/binary>>, [object|Stack], Callbacks, Opts) ->
-    maybe_done(Rest, Stack, fold(end_object, Callbacks), Opts);
-maybe_done(<<?end_array, Rest/binary>>, [array|Stack], Callbacks, Opts) ->
-    maybe_done(Rest, Stack, fold(end_array, Callbacks), Opts);
-maybe_done(<<?comma, Rest/binary>>, [object|Stack], Callbacks, Opts) ->
-    key(Rest, [key|Stack], Callbacks, Opts);
-maybe_done(<<?comma, Rest/binary>>, [array|_] = Stack, Callbacks, Opts) ->
-    value(Rest, Stack, Callbacks, Opts);
-maybe_done(<<?solidus, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
-    maybe_comment(Rest, fun(Resume) -> maybe_done(Resume, Stack, Callbacks, Opts) end);
-maybe_done(<<>>, [], Callbacks, Opts) ->
-    {fold(end_of_stream, Callbacks), fun(Stream) -> maybe_done(Stream, [], Callbacks, Opts) end};
-maybe_done(<<>>, Stack, Callbacks, Opts) ->
-    {incomplete, fun(Stream) -> maybe_done(Stream, Stack, Callbacks, Opts) end}.
-
-
-object(<<S, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) ->
-    object(Rest, Stack, Callbacks, Opts);
-object(<<?quote, Rest/binary>>, Stack, Callbacks, Opts) ->
-    string(Rest, Stack, Callbacks, Opts, []);
-object(<<?end_object, Rest/binary>>, [key|Stack], Callbacks, Opts) ->
-    maybe_done(Rest, Stack, fold(end_object, Callbacks), Opts);
-object(<<?solidus, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
-    maybe_comment(Rest, fun(Resume) -> object(Resume, Stack, Callbacks, Opts) end);
-object(<<>>, Stack, Callbacks, Opts) ->
-    {incomplete, fun(Stream) -> object(Stream, Stack, Callbacks, Opts) end}.
-
-
-array(<<S, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) -> 
-    array(Rest, Stack, Callbacks, Opts);       
-array(<<?quote, Rest/binary>>, Stack, Callbacks, Opts) ->
-    string(Rest, Stack, Callbacks, Opts, []);
-array(<<$t, Rest/binary>>, Stack, Callbacks, Opts) ->
-    tr(Rest, Stack, Callbacks, Opts);
-array(<<$f, Rest/binary>>, Stack, Callbacks, Opts) ->
-    fa(Rest, Stack, Callbacks, Opts);
-array(<<$n, Rest/binary>>, Stack, Callbacks, Opts) ->
-    nu(Rest, Stack, Callbacks, Opts);
-array(<<?negative, Rest/binary>>, Stack, Callbacks, Opts) ->
-    negative(Rest, Stack, Callbacks, Opts, "-");
-array(<<?zero, Rest/binary>>, Stack, Callbacks, Opts) ->
-    zero(Rest, Stack, Callbacks, Opts, "0");
-array(<<S, Rest/binary>>, Stack, Callbacks, Opts) when ?is_nonzero(S) ->
-    integer(Rest, Stack, Callbacks, Opts, [S]);
-array(<<?start_object, Rest/binary>>, Stack, Callbacks, Opts) ->
-    object(Rest, [key|Stack], fold(start_object, Callbacks), Opts);
-array(<<?start_array, Rest/binary>>, Stack, Callbacks, Opts) ->
-    array(Rest, [array|Stack], fold(start_array, Callbacks), Opts);
-array(<<?end_array, Rest/binary>>, [array|Stack], Callbacks, Opts) ->
-    maybe_done(Rest, Stack, fold(end_array, Callbacks), Opts);
-array(<<?solidus, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
-    maybe_comment(Rest, fun(Resume) -> array(Resume, Stack, Callbacks, Opts) end);
-array(<<>>, Stack, Callbacks, Opts) ->
-    {incomplete, fun(Stream) -> array(Stream, Stack, Callbacks, Opts) end}.  
-
-
-value(<<S, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) -> 
-    value(Rest, Stack, Callbacks, Opts);
-value(<<?quote, Rest/binary>>, Stack, Callbacks, Opts) ->
-    string(Rest, Stack, Callbacks, Opts, []);
-value(<<$t, Rest/binary>>, Stack, Callbacks, Opts) ->
-    tr(Rest, Stack, Callbacks, Opts);
-value(<<$f, Rest/binary>>, Stack, Callbacks, Opts) ->
-    fa(Rest, Stack, Callbacks, Opts);
-value(<<$n, Rest/binary>>, Stack, Callbacks, Opts) ->
-    nu(Rest, Stack, Callbacks, Opts);
-value(<<?negative, Rest/binary>>, Stack, Callbacks, Opts) ->
-    negative(Rest, Stack, Callbacks, Opts, "-");
-value(<<?zero, Rest/binary>>, Stack, Callbacks, Opts) ->
-    zero(Rest, Stack, Callbacks, Opts, "0");
-value(<<S, Rest/binary>>, Stack, Callbacks, Opts) when ?is_nonzero(S) ->
-    integer(Rest, Stack, Callbacks, Opts, [S]);
-value(<<?start_object, Rest/binary>>, Stack, Callbacks, Opts) ->
-    object(Rest, [key|Stack], fold(start_object, Callbacks), Opts);
-value(<<?start_array, Rest/binary>>, Stack, Callbacks, Opts) ->
-    array(Rest, [array|Stack], fold(start_array, Callbacks), Opts);
-value(<<?solidus, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
-    maybe_comment(Rest, fun(Resume) -> value(Resume, Stack, Callbacks, Opts) end);
-value(<<>>, Stack, Callbacks, Opts) ->
-    {incomplete, fun(Stream) -> value(Stream, Stack, Callbacks, Opts) end}.
-
-
-colon(<<S, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) ->
-    colon(Rest, Stack, Callbacks, Opts);
-colon(<<?colon, Rest/binary>>, [key|Stack], Callbacks, Opts) ->
-    value(Rest, [object|Stack], Callbacks, Opts);
-colon(<<?solidus, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
-    maybe_comment(Rest, fun(Resume) -> colon(Resume, Stack, Callbacks, Opts) end);
-colon(<<>>, Stack, Callbacks, Opts) ->
-    {incomplete, fun(Stream) -> colon(Stream, Stack, Callbacks, Opts) end}.
-
-
-key(<<S, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) ->
-    key(Rest, Stack, Callbacks, Opts);        
-key(<<?quote, Rest/binary>>, Stack, Callbacks, Opts) ->
-    string(Rest, Stack, Callbacks, Opts, []);
-key(<<?solidus, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
-    maybe_comment(Rest, fun(Resume) -> key(Resume, Stack, Callbacks, Opts) end);
-key(<<>>, Stack, Callbacks, Opts) ->
-    {incomplete, fun(Stream) -> key(Stream, Stack, Callbacks, Opts) end}.
-
-
-%% string has an additional parameter, an accumulator (Acc) used to hold the intermediate
-%%   representation of the string being parsed. using a list of integers representing
-%%   unicode codepoints is faster than constructing binaries, many of which will be
-%%   converted back to lists by the user anyways.
-
-%% the clause starting with Bin is necessary for cases where a stream is broken at a
-%%   point where it contains only a partial utf-8 sequence.
-
-string(<<?quote, Rest/binary>>, [key|_] = Stack, Callbacks, Opts, Acc) ->
-    colon(Rest, Stack, fold({key, lists:reverse(Acc)}, Callbacks), Opts);
-string(<<?quote, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
-    maybe_done(Rest, Stack, fold({string, lists:reverse(Acc)}, Callbacks), Opts);
-string(<<?rsolidus, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
-    escape(Rest, Stack, Callbacks, Opts, Acc);   
-string(<<S/utf8, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_noncontrol(S) ->
-    string(Rest, Stack, Callbacks, Opts, [S] ++ Acc);   
-string(Bin, Stack, Callbacks, Opts, Acc) ->
-    {incomplete, fun(Stream) -> string(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
-
-
-%% only thing to note here is the additional accumulator passed to escaped_unicode used
-%%   to hold the codepoint sequence. unescessary, but nicer than using the string 
-%%   accumulator. 
-
-escape(<<$b, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
-    string(Rest, Stack, Callbacks, Opts, "\b" ++ Acc);
-escape(<<$f, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
-    string(Rest, Stack, Callbacks, Opts, "\f" ++ Acc);
-escape(<<$n, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
-    string(Rest, Stack, Callbacks, Opts, "\n" ++ Acc);
-escape(<<$r, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
-    string(Rest, Stack, Callbacks, Opts, "\r" ++ Acc);
-escape(<<$t, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
-    string(Rest, Stack, Callbacks, Opts, "\t" ++ Acc);
-escape(<<$u, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
-    escaped_unicode(Rest, Stack, Callbacks, Opts, Acc, []);      
-escape(<<S, Rest/binary>>, Stack, Callbacks, Opts, Acc) 
-        when S =:= ?quote; S =:= ?solidus; S =:= ?rsolidus ->
-    string(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
-escape(<<>>, Stack, Callbacks, Opts, Acc) ->
-    {incomplete, fun(Stream) -> escape(Stream, Stack, Callbacks, Opts, Acc) end}.
-
-
-%% this code is ugly and unfortunate, but so is json's handling of escaped unicode
-%%   codepoint sequences. if the ascii option is present, the sequence is converted
-%%   to a codepoint and inserted into the string if it represents an ascii value. if 
-%%   the codepoint option is present the sequence is converted and inserted as long
-%%   as it represents a valid unicode codepoint. this means non-characters 
-%%   representable in 16 bits are not converted (the utf16 surrogates and the two
-%%   special non-characters). any other option and no conversion is done.
-
-escaped_unicode(<<D, Rest/binary>>, 
-        Stack, 
-        Callbacks, 
-        ?escaped_unicode_to_ascii(Opts), 
-        String, 
-        [C, B, A]) 
-            when ?is_hex(D) ->
-    case erlang:list_to_integer([A, B, C, D], 16) of
-        X when X < 128 ->
-            string(Rest, Stack, Callbacks, Opts, [X] ++ String)
-        ; _ ->
-            string(Rest, Stack, Callbacks, Opts, [D, C, B, A, $u, ?rsolidus] ++ String)
+%% utf32-big null order detection
+detect_encoding(<<0, 0, 0, X, _Rest/binary>> = JSON, Stack, Callbacks, Opts) when X =/= 0 ->
+    jsx_utf32:start(JSON, Stack, Callbacks, Opts);
+    
+%% trying to parse a json string of a single character encoded in utf8 will fail
+%%   unless special cased
+detect_encoding(<<X>> = JSON, Stack, Callbacks, Opts) when X =/= 0 ->
+    try jsx_utf8:start(JSON, Stack, Callbacks, Opts)
+    catch error:function_clause ->
+        {incomplete, 
+            fun(Stream) -> 
+                detect_encoding(<<X, Stream/binary>>, Stack, Callbacks, Opts) 
+            end
+        }
     end;
-escaped_unicode(<<D, Rest/binary>>, 
-        Stack, 
-        Callbacks, 
-        ?escaped_unicode_to_codepoint(Opts), 
-        String, 
-        [C, B, A]) 
-            when ?is_hex(D) ->
-    case erlang:list_to_integer([A, B, C, D], 16) of
-        X when X < 16#d800; X > 16#dfff, X < 16#fffe ->
-            string(Rest, Stack, Callbacks, Opts, [X] ++ String)
-        ; _ ->
-            string(Rest, Stack, Callbacks, Opts, [D, C, B, A, $u, ?rsolidus] ++ String)
-    end;
-escaped_unicode(<<D, Rest/binary>>, Stack, Callbacks, Opts, String, [C, B, A]) when ?is_hex(D) ->
-    string(Rest, Stack, Callbacks, Opts, [D, C, B, A, $u, ?rsolidus] ++ String);
-escaped_unicode(<<S, Rest/binary>>, Stack, Callbacks, Opts, String, Acc) when ?is_hex(S) ->
-    escaped_unicode(Rest, Stack, Callbacks, Opts, String, [S] ++ Acc);
-escaped_unicode(<<>>, Stack, Callbacks, Opts, String, Acc) ->
-    {incomplete, fun(Stream) -> escaped_unicode(Stream, Stack, Callbacks, Opts, String, Acc) end}.
-
-
-%% like strings, numbers are collected in an intermediate accumulator before
-%%   being emitted to the callback handler. no processing of numbers is done in
-%%   process, it's left for the user, though there are convenience functions to
-%%   convert them into erlang floats/integers in jsx_utils.erl.
-
-%% TODO: actually write that jsx_utils.erl module mentioned above...
-
-negative(<<$0, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
-    zero(Rest, Stack, Callbacks, Opts, "0" ++ Acc);
-negative(<<S, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_nonzero(S) ->
-    integer(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
-negative(<<>>, Stack, Callbacks, Opts, Acc) ->
-    {incomplete, fun(Stream) -> negative(Stream, Stack, Callbacks, Opts, Acc) end}.
-
-
-zero(<<?end_object, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
-    maybe_done(Rest, Stack, fold(end_object, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
-zero(<<?end_array, Rest/binary>>, [array|Stack], Callbacks, Opts, Acc) ->
-    maybe_done(Rest, Stack, fold(end_array, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
-zero(<<?comma, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
-    key(Rest, [key|Stack], fold({number, lists:reverse(Acc)}, Callbacks), Opts);
-zero(<<?comma, Rest/binary>>, [array|_] = Stack, Callbacks, Opts, Acc) ->
-    value(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
-zero(<<?decimalpoint, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
-    fraction(Rest, Stack, Callbacks, Opts, [?decimalpoint] ++ Acc);
-zero(<<S, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_whitespace(S) ->
-    maybe_done(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
-zero(<<?solidus, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts), Acc) ->
-    maybe_comment(Rest, fun(Resume) -> zero(Resume, Stack, Callbacks, Opts, Acc) end);
-zero(<<>>, [], Callbacks, Opts, Acc) ->
-    {fold(end_of_stream, fold({number, lists:reverse(Acc)}, Callbacks)), 
-        fun(Stream) -> zero(Stream, [], Callbacks, Opts, Acc) end};
-zero(<<>>, Stack, Callbacks, Opts, Acc) ->
-    {incomplete, fun(Stream) -> zero(Stream, Stack, Callbacks, Opts, Acc) end}.
-
-
-integer(<<S, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_nonzero(S) ->
-    integer(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
-integer(<<?end_object, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
-    maybe_done(Rest, Stack, fold(end_object, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
-integer(<<?end_array, Rest/binary>>, [array|Stack], Callbacks, Opts, Acc) ->
-    maybe_done(Rest, Stack, fold(end_array, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
-integer(<<?comma, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
-    key(Rest, [key|Stack], fold({number, lists:reverse(Acc)}, Callbacks), Opts);
-integer(<<?comma, Rest/binary>>, [array|_] = Stack, Callbacks, Opts, Acc) ->
-    value(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
-integer(<<?decimalpoint, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
-    fraction(Rest, Stack, Callbacks, Opts, [?decimalpoint] ++ Acc);
-integer(<<?zero, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
-    integer(Rest, Stack, Callbacks, Opts, [?zero] ++ Acc);
-integer(<<$e, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
-    e(Rest, Stack, Callbacks, Opts, "e" ++ Acc);
-integer(<<$E, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
-    e(Rest, Stack, Callbacks, Opts, "e" ++ Acc);
-integer(<<S, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_whitespace(S) ->
-    maybe_done(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
-integer(<<?solidus, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts), Acc) ->
-    maybe_comment(Rest, fun(Resume) -> integer(Resume, Stack, Callbacks, Opts, Acc) end);
-integer(<<>>, [], Callbacks, Opts, Acc) ->
-    {fold(end_of_stream, fold({number, lists:reverse(Acc)}, Callbacks)), 
-        fun(Stream) -> integer(Stream, [], Callbacks, Opts, Acc) end};
-integer(<<>>, Stack, Callbacks, Opts, Acc) ->
-    {incomplete, fun(Stream) -> integer(Stream, Stack, Callbacks, Opts, Acc) end}.
-
-fraction(<<S, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_nonzero(S) ->
-    fraction(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
-fraction(<<?end_object, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
-    maybe_done(Rest, Stack, fold(end_object, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
-fraction(<<?end_array, Rest/binary>>, [array|Stack], Callbacks, Opts, Acc) ->
-    maybe_done(Rest, Stack, fold(end_array, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
-fraction(<<?comma, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
-    key(Rest, [key|Stack], fold({number, lists:reverse(Acc)}, Callbacks), Opts);
-fraction(<<?comma, Rest/binary>>, [array|_] = Stack, Callbacks, Opts, Acc) ->
-    value(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
-fraction(<<?zero, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
-    fraction(Rest, Stack, Callbacks, Opts, [?zero] ++ Acc);
-fraction(<<$e, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
-    e(Rest, Stack, Callbacks, Opts, "e" ++ Acc);
-fraction(<<$E, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
-    e(Rest, Stack, Callbacks, Opts, "e" ++ Acc);
-fraction(<<S, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_whitespace(S) ->
-    maybe_done(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
-fraction(<<?solidus, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts), Acc) ->
-    maybe_comment(Rest, fun(Resume) -> fraction(Resume, Stack, Callbacks, Opts, Acc) end);
-fraction(<<>>, [], Callbacks, Opts, Acc) ->
-    {fold(end_of_stream, fold({number, lists:reverse(Acc)}, Callbacks)), 
-        fun(Stream) -> fraction(Stream, [], Callbacks, Opts, Acc) end};
-fraction(<<>>, Stack, Callbacks, Opts, Acc) ->
-    {incomplete, fun(Stream) -> fraction(Stream, Stack, Callbacks, Opts, Acc) end}.
-
-
-e(<<S, Rest/binary>>, Stack, Callbacks, Opts, Acc) when S =:= ?zero; ?is_nonzero(S) ->
-    exp(Rest, Stack, Callbacks, Opts, [S] ++ Acc);   
-e(<<S, Rest/binary>>, Stack, Callbacks, Opts, Acc) when S =:= ?positive; S =:= ?negative ->
-    ex(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
-e(<<>>, Stack, Callbacks, Opts, Acc) ->
-    {incomplete, fun(Stream) -> e(Stream, Stack, Callbacks, Opts, Acc) end}.
-
-
-ex(<<S, Rest/binary>>, Stack, Callbacks, Opts, Acc) when S =:= ?zero; ?is_nonzero(S) ->
-    exp(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
-ex(<<>>, Stack, Callbacks, Opts, Acc) ->
-    {incomplete, fun(Stream) -> ex(Stream, Stack, Callbacks, Opts, Acc) end}.
-
-
-exp(<<S, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_nonzero(S) ->
-    exp(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
-exp(<<?end_object, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
-    maybe_done(Rest, Stack, fold(end_object, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
-exp(<<?end_array, Rest/binary>>, [array|Stack], Callbacks, Opts, Acc) ->
-    maybe_done(Rest, Stack, fold(end_array, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
-exp(<<?comma, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
-    key(Rest, [key|Stack], fold({number, lists:reverse(Acc)}, Callbacks), Opts);
-exp(<<?comma, Rest/binary>>, [array|_] = Stack, Callbacks, Opts, Acc) ->
-    value(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
-exp(<<?zero, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
-    exp(Rest, Stack, Callbacks, Opts, [?zero] ++ Acc);
-exp(<<?solidus, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts), Acc) ->
-    maybe_comment(Rest, fun(Resume) -> exp(Resume, Stack, Callbacks, Opts, Acc) end);
-exp(<<S, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_whitespace(S) ->
-    maybe_done(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
-exp(<<>>, [], Callbacks, Opts, Acc) ->
-    {fold(end_of_stream, fold({number, lists:reverse(Acc)}, Callbacks)), 
-        fun(Stream) -> exp(Stream, [], Callbacks, Opts, Acc) end};
-exp(<<>>, Stack, Callbacks, Opts, Acc) ->
-    {incomplete, fun(Stream) -> exp(Stream, Stack, Callbacks, Opts, Acc) end}.
-
-
-tr(<<$r, Rest/binary>>, Stack, Callbacks, Opts) ->
-    tru(Rest, Stack, Callbacks, Opts);
-tr(<<>>, Stack, Callbacks, Opts) ->
-    {incomplete, fun(Stream) -> tr(Stream, Stack, Callbacks, Opts) end}.
-
-
-tru(<<$u, Rest/binary>>, Stack, Callbacks, Opts) ->
-    true(Rest, Stack, Callbacks, Opts);
-tru(<<>>, Stack, Callbacks, Opts) ->
-    {incomplete, fun(Stream) -> tru(Stream, Stack, Callbacks, Opts) end}.
-
-
-true(<<$e, Rest/binary>>, Stack, Callbacks, Opts) ->
-    maybe_done(Rest, Stack, fold({literal, true}, Callbacks), Opts);
-true(<<>>, Stack, Callbacks, Opts) ->
-    {incomplete, fun(Stream) -> true(Stream, Stack, Callbacks, Opts) end}.
-
-
-fa(<<$a, Rest/binary>>, Stack, Callbacks, Opts) ->
-    fal(Rest, Stack, Callbacks, Opts);
-fa(<<>>, Stack, Callbacks, Opts) ->
-    {incomplete, fun(Stream) -> fa(Stream, Stack, Callbacks, Opts) end}.
-
-
-fal(<<$l, Rest/binary>>, Stack, Callbacks, Opts) ->
-    fals(Rest, Stack, Callbacks, Opts);
-fal(<<>>, Stack, Callbacks, Opts) ->
-    {incomplete, fun(Stream) -> fal(Stream, Stack, Callbacks, Opts) end}.
-
-
-fals(<<$s, Rest/binary>>, Stack, Callbacks, Opts) ->
-    false(Rest, Stack, Callbacks, Opts);
-fals(<<>>, Stack, Callbacks, Opts) ->
-    {incomplete, fun(Stream) -> fals(Stream, Stack, Callbacks, Opts) end}.
-
-
-false(<<$e, Rest/binary>>, Stack, Callbacks, Opts) ->
-    maybe_done(Rest, Stack, fold({literal, false}, Callbacks), Opts);
-false(<<>>, Stack, Callbacks, Opts) ->
-    {incomplete, fun(Stream) -> false(Stream, Stack, Callbacks, Opts) end}.
-
-
-nu(<<$u, Rest/binary>>, Stack, Callbacks, Opts) ->
-    nul(Rest, Stack, Callbacks, Opts);
-nu(<<>>, Stack, Callbacks, Opts) ->
-    {incomplete, fun(Stream) -> nu(Stream, Stack, Callbacks, Opts) end}.
-
-
-nul(<<$l, Rest/binary>>, Stack, Callbacks, Opts) ->
-    null(Rest, Stack, Callbacks, Opts);
-nul(<<>>, Stack, Callbacks, Opts) ->
-    {incomplete, fun(Stream) -> nul(Stream, Stack, Callbacks, Opts) end}.
-
-
-null(<<$l, Rest/binary>>, Stack, Callbacks, Opts) ->
-    maybe_done(Rest, Stack, fold({literal, null}, Callbacks), Opts);
-null(<<>>, Stack, Callbacks, Opts) ->
-    {incomplete, fun(Stream) -> null(Stream, Stack, Callbacks, Opts) end}.    
-
-
-%% comments are c style, /* blah blah */ and are STRONGLY discouraged. any unicode
-%%   character is valid in a comment, except, obviously the */ sequence which ends
-%%   the comment. they're implemented as a closure called when the comment ends that
-%%   returns execution to the point where the comment began. comments are not 
-%%   recorded in any way, simply parsed.    
-
-maybe_comment(<<?star, Rest/binary>>, Resume) ->
-    comment(Rest, Resume);
-maybe_comment(<<>>, Resume) ->
-    {incomplete, fun(Stream) -> maybe_comment(Stream, Resume) end}.
-
-
-comment(<<?star, Rest/binary>>, Resume) ->
-    maybe_comment_done(Rest, Resume);
-comment(<<_/utf8, Rest/binary>>, Resume) ->
-    comment(Rest, Resume);
-comment(<<>>, Resume) ->
-    {incomplete, fun(Stream) -> comment(Stream, Resume) end}.
-
-
-maybe_comment_done(<<?solidus, Rest/binary>>, Resume) ->
-    Resume(Rest);
-maybe_comment_done(<<>>, Resume) ->
-    {incomplete, fun(Stream) -> maybe_comment_done(Stream, Resume) end}.
-
-
-%% callbacks to our handler are roughly equivalent to a fold over the events, incremental
-%%   rather than all at once.    
-
-fold(end_of_stream, {F, State}) ->
-    F(end_of_stream, State);
-fold(Event, {F, State}) when is_function(F) ->
-    {F, F(Event, State)}.
-
-
+    
+%% not enough input, request more
+detect_encoding(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, 
+        fun(Stream) -> 
+            detect_encoding(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) 
+        end
+    }.
\ No newline at end of file
diff --git a/src/jsx_common.hrl b/src/jsx_common.hrl
new file mode 100644
index 0000000..510407b
--- /dev/null
+++ b/src/jsx_common.hrl
@@ -0,0 +1,83 @@
+%% The MIT License
+
+%% Copyright (c) 2010 Alisdair Sullivan <alisdairsullivan@yahoo.ca>
+
+%% Permission is hereby granted, free of charge, to any person obtaining a copy
+%% of this software and associated documentation files (the "Software"), to deal
+%% in the Software without restriction, including without limitation the rights
+%% to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+%% copies of the Software, and to permit persons to whom the Software is
+%% furnished to do so, subject to the following conditions:
+
+%% The above copyright notice and this permission notice shall be included in
+%% all copies or substantial portions of the Software.
+
+%% THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+%% IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+%% FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+%% AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+%% LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+%% OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+%% THE SOFTWARE.
+
+%% option flags
+
+-define(comments_enabled(X), {true, _} = X).
+-define(escaped_unicode_to_ascii(X), {_, ascii} = X).
+-define(escaped_unicode_to_codepoint(X), {_, codepoint} = X).
+
+%% whitespace
+-define(space, 16#20).
+-define(tab, 16#09).
+-define(cr, 16#0D).
+-define(newline, 16#0A).
+
+%% object delimiters
+-define(start_object, 16#7B).
+-define(end_object, 16#7D).
+
+%% array delimiters
+-define(start_array, 16#5B).
+-define(end_array, 16#5D).
+
+%% kv seperator
+-define(comma, 16#2C).
+-define(quote, 16#22).
+-define(colon, 16#3A).
+
+%% string escape sequences
+-define(escape, 16#5C).
+-define(rsolidus, 16#5C).
+-define(solidus, 16#2F).
+-define(formfeed, 16#0C).
+-define(backspace, 16#08).
+-define(unicode, 16#75).
+
+%% math
+-define(zero, 16#30).
+-define(decimalpoint, 16#2E).
+-define(negative, 16#2D).
+-define(positive, 16#2B).
+
+%% comments
+-define(star, 16#2a).
+
+-define(is_hex(Symbol),
+    (Symbol >= $a andalso Symbol =< $z); (Symbol >= $A andalso Symbol =< $Z); 
+        (Symbol >= $0 andalso Symbol =< $9)
+).
+
+-define(is_nonzero(Symbol),
+    Symbol >= $1 andalso Symbol =< $9
+).
+
+-define(is_noncontrol(Symbol),
+    Symbol >= ?space
+).
+
+-define(is_whitespace(Symbol),
+    Symbol =:= ?space; Symbol =:= ?tab; Symbol =:= ?cr; Symbol =:= ?newline
+).
+    
+    
+
diff --git a/src/jsx_utf16.erl b/src/jsx_utf16.erl
new file mode 100644
index 0000000..75bd0db
--- /dev/null
+++ b/src/jsx_utf16.erl
@@ -0,0 +1,476 @@
+%% The MIT License
+
+%% Copyright (c) 2010 Alisdair Sullivan <alisdairsullivan@yahoo.ca>
+
+%% Permission is hereby granted, free of charge, to any person obtaining a copy
+%% of this software and associated documentation files (the "Software"), to deal
+%% in the Software without restriction, including without limitation the rights
+%% to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+%% copies of the Software, and to permit persons to whom the Software is
+%% furnished to do so, subject to the following conditions:
+
+%% The above copyright notice and this permission notice shall be included in
+%% all copies or substantial portions of the Software.
+
+%% THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+%% IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+%% FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+%% AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+%% LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+%% OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+%% THE SOFTWARE.
+
+-module(jsx_utf16).
+-author("alisdairsullivan@yahoo.ca").
+
+-include("jsx_common.hrl").
+
+-export([start/4]).
+
+-define(encoding, utf16).
+
+
+%% callbacks to our handler are roughly equivalent to a fold over the events, incremental
+%%   rather than all at once.    
+
+fold(end_of_stream, {F, State}) ->
+    F(end_of_stream, State);
+fold(Event, {F, State}) when is_function(F) ->
+    {F, F(Event, State)}.
+
+
+%% this code is mostly autogenerated and mostly ugly. apologies. for more insight on
+%%   Callbacks or Opts, see the comments accompanying decoder/2 (in jsx.erl). Stack 
+%%   is a stack of flags used to track depth and to keep track of whether we are 
+%%   returning from a value or a key inside objects. all pops, peeks and pushes are 
+%%   inlined. the code that handles naked values and comments is not optimized by the 
+%%   compiler for efficient matching, but you shouldn't be using naked values or comments 
+%%   anyways, they are horrible and contrary to the spec.
+
+start(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) -> 
+    start(Rest, Stack, Callbacks, Opts);
+start(<<?start_object/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    object(Rest, [key|Stack], fold(start_object, Callbacks), Opts);
+start(<<?start_array/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    array(Rest, [array|Stack], fold(start_array, Callbacks), Opts);
+start(<<?quote/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    string(Rest, Stack, Callbacks, Opts, []);
+start(<<$t/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    tr(Rest, Stack, Callbacks, Opts);
+start(<<$f/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    fa(Rest, Stack, Callbacks, Opts);
+start(<<$n/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    nu(Rest, Stack, Callbacks, Opts);
+start(<<?negative/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    negative(Rest, Stack, Callbacks, Opts, "-");
+start(<<?zero/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    zero(Rest, Stack, Callbacks, Opts, "0");
+start(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_nonzero(S) ->
+    integer(Rest, Stack, Callbacks, Opts, [S]);
+start(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
+    maybe_comment(Rest, fun(Resume) -> start(Resume, Stack, Callbacks, Opts) end);
+start(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> start(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+maybe_done(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) ->
+    maybe_done(Rest, Stack, Callbacks, Opts);
+maybe_done(<<?end_object/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts) ->
+    maybe_done(Rest, Stack, fold(end_object, Callbacks), Opts);
+maybe_done(<<?end_array/?encoding, Rest/binary>>, [array|Stack], Callbacks, Opts) ->
+    maybe_done(Rest, Stack, fold(end_array, Callbacks), Opts);
+maybe_done(<<?comma/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts) ->
+    key(Rest, [key|Stack], Callbacks, Opts);
+maybe_done(<<?comma/?encoding, Rest/binary>>, [array|_] = Stack, Callbacks, Opts) ->
+    value(Rest, Stack, Callbacks, Opts);
+maybe_done(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
+    maybe_comment(Rest, fun(Resume) -> maybe_done(Resume, Stack, Callbacks, Opts) end);
+maybe_done(<<>>, [], Callbacks, Opts) ->
+    {fold(end_of_stream, Callbacks), fun(Stream) -> maybe_done(Stream, [], Callbacks, Opts) end};
+maybe_done(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> maybe_done(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+object(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) ->
+    object(Rest, Stack, Callbacks, Opts);
+object(<<?quote/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    string(Rest, Stack, Callbacks, Opts, []);
+object(<<?end_object/?encoding, Rest/binary>>, [key|Stack], Callbacks, Opts) ->
+    maybe_done(Rest, Stack, fold(end_object, Callbacks), Opts);
+object(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
+    maybe_comment(Rest, fun(Resume) -> object(Resume, Stack, Callbacks, Opts) end);
+object(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> object(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+array(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) -> 
+    array(Rest, Stack, Callbacks, Opts);       
+array(<<?quote/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    string(Rest, Stack, Callbacks, Opts, []);
+array(<<$t/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    tr(Rest, Stack, Callbacks, Opts);
+array(<<$f/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    fa(Rest, Stack, Callbacks, Opts);
+array(<<$n/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    nu(Rest, Stack, Callbacks, Opts);
+array(<<?negative/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    negative(Rest, Stack, Callbacks, Opts, "-");
+array(<<?zero/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    zero(Rest, Stack, Callbacks, Opts, "0");
+array(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_nonzero(S) ->
+    integer(Rest, Stack, Callbacks, Opts, [S]);
+array(<<?start_object/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    object(Rest, [key|Stack], fold(start_object, Callbacks), Opts);
+array(<<?start_array/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    array(Rest, [array|Stack], fold(start_array, Callbacks), Opts);
+array(<<?end_array/?encoding, Rest/binary>>, [array|Stack], Callbacks, Opts) ->
+    maybe_done(Rest, Stack, fold(end_array, Callbacks), Opts);
+array(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
+    maybe_comment(Rest, fun(Resume) -> array(Resume, Stack, Callbacks, Opts) end);
+array(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> array(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.  
+
+
+value(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) -> 
+    value(Rest, Stack, Callbacks, Opts);
+value(<<?quote/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    string(Rest, Stack, Callbacks, Opts, []);
+value(<<$t/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    tr(Rest, Stack, Callbacks, Opts);
+value(<<$f/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    fa(Rest, Stack, Callbacks, Opts);
+value(<<$n/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    nu(Rest, Stack, Callbacks, Opts);
+value(<<?negative/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    negative(Rest, Stack, Callbacks, Opts, "-");
+value(<<?zero/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    zero(Rest, Stack, Callbacks, Opts, "0");
+value(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_nonzero(S) ->
+    integer(Rest, Stack, Callbacks, Opts, [S]);
+value(<<?start_object/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    object(Rest, [key|Stack], fold(start_object, Callbacks), Opts);
+value(<<?start_array/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    array(Rest, [array|Stack], fold(start_array, Callbacks), Opts);
+value(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
+    maybe_comment(Rest, fun(Resume) -> value(Resume, Stack, Callbacks, Opts) end);
+value(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> value(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+colon(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) ->
+    colon(Rest, Stack, Callbacks, Opts);
+colon(<<?colon/?encoding, Rest/binary>>, [key|Stack], Callbacks, Opts) ->
+    value(Rest, [object|Stack], Callbacks, Opts);
+colon(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
+    maybe_comment(Rest, fun(Resume) -> colon(Resume, Stack, Callbacks, Opts) end);
+colon(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> colon(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+key(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) ->
+    key(Rest, Stack, Callbacks, Opts);        
+key(<<?quote/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    string(Rest, Stack, Callbacks, Opts, []);
+key(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
+    maybe_comment(Rest, fun(Resume) -> key(Resume, Stack, Callbacks, Opts) end);
+key(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> key(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+%% string has an additional parameter, an accumulator (Acc) used to hold the intermediate
+%%   representation of the string being parsed. using a list of integers representing
+%%   unicode codepoints is faster than constructing binaries, many of which will be
+%%   converted back to lists by the user anyways.
+
+%% the clause starting with Bin is necessary for cases where a stream is broken at a
+%%   point where it contains only a partial utf-8 sequence.
+
+string(<<?quote/?encoding, Rest/binary>>, [key|_] = Stack, Callbacks, Opts, Acc) ->
+    colon(Rest, Stack, fold({key, lists:reverse(Acc)}, Callbacks), Opts);
+string(<<?quote/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold({string, lists:reverse(Acc)}, Callbacks), Opts);
+string(<<?rsolidus/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    escape(Rest, Stack, Callbacks, Opts, Acc);   
+string(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_noncontrol(S) ->
+    string(Rest, Stack, Callbacks, Opts, [S] ++ Acc);   
+string(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> string(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+%% only thing to note here is the additional accumulator passed to escaped_unicode used
+%%   to hold the codepoint sequence. unescessary, but nicer than using the string 
+%%   accumulator. 
+
+escape(<<$b/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    string(Rest, Stack, Callbacks, Opts, "\b" ++ Acc);
+escape(<<$f/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    string(Rest, Stack, Callbacks, Opts, "\f" ++ Acc);
+escape(<<$n/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    string(Rest, Stack, Callbacks, Opts, "\n" ++ Acc);
+escape(<<$r/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    string(Rest, Stack, Callbacks, Opts, "\r" ++ Acc);
+escape(<<$t/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    string(Rest, Stack, Callbacks, Opts, "\t" ++ Acc);
+escape(<<$u/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    escaped_unicode(Rest, Stack, Callbacks, Opts, Acc, []);      
+escape(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) 
+        when S =:= ?quote; S =:= ?solidus; S =:= ?rsolidus ->
+    string(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
+escape(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> escape(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+%% this code is ugly and unfortunate, but so is json's handling of escaped unicode
+%%   codepoint sequences. if the ascii option is present, the sequence is converted
+%%   to a codepoint and inserted into the string if it represents an ascii value. if 
+%%   the codepoint option is present the sequence is converted and inserted as long
+%%   as it represents a valid unicode codepoint. this means non-characters 
+%%   representable in 16 bits are not converted (the utf16 surrogates and the two
+%%   special non-characters). any other option and no conversion is done.
+
+escaped_unicode(<<D/?encoding, Rest/binary>>, 
+        Stack, 
+        Callbacks, 
+        ?escaped_unicode_to_ascii(Opts), 
+        String, 
+        [C, B, A]) 
+            when ?is_hex(D) ->
+    case erlang:list_to_integer([A, B, C, D], 16) of
+        X when X < 128 ->
+            string(Rest, Stack, Callbacks, Opts, [X] ++ String)
+        ; _ ->
+            string(Rest, Stack, Callbacks, Opts, [D, C, B, A, $u, ?rsolidus] ++ String)
+    end;
+escaped_unicode(<<D/?encoding, Rest/binary>>, 
+        Stack, 
+        Callbacks, 
+        ?escaped_unicode_to_codepoint(Opts), 
+        String, 
+        [C, B, A]) 
+            when ?is_hex(D) ->
+    case erlang:list_to_integer([A, B, C, D], 16) of
+        X when X < 16#d800; X > 16#dfff, X < 16#fffe ->
+            string(Rest, Stack, Callbacks, Opts, [X] ++ String)
+        ; _ ->
+            string(Rest, Stack, Callbacks, Opts, [D, C, B, A, $u, ?rsolidus] ++ String)
+    end;
+escaped_unicode(<<D/?encoding, Rest/binary>>, Stack, Callbacks, Opts, String, [C, B, A]) when ?is_hex(D) ->
+    string(Rest, Stack, Callbacks, Opts, [D, C, B, A, $u, ?rsolidus] ++ String);
+escaped_unicode(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, String, Acc) when ?is_hex(S) ->
+    escaped_unicode(Rest, Stack, Callbacks, Opts, String, [S] ++ Acc);
+escaped_unicode(Bin, Stack, Callbacks, Opts, String, Acc) ->
+    {incomplete, fun(Stream) -> escaped_unicode(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, String, Acc) end}.
+
+
+%% like strings, numbers are collected in an intermediate accumulator before
+%%   being emitted to the callback handler. no processing of numbers is done in
+%%   process, it's left for the user, though there are convenience functions to
+%%   convert them into erlang floats/integers in jsx_utils.erl.
+
+%% TODO: actually write that jsx_utils.erl module mentioned above...
+
+negative(<<$0/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    zero(Rest, Stack, Callbacks, Opts, "0" ++ Acc);
+negative(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_nonzero(S) ->
+    integer(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
+negative(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> negative(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+zero(<<?end_object/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_object, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+zero(<<?end_array/?encoding, Rest/binary>>, [array|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_array, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+zero(<<?comma/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    key(Rest, [key|Stack], fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+zero(<<?comma/?encoding, Rest/binary>>, [array|_] = Stack, Callbacks, Opts, Acc) ->
+    value(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+zero(<<?decimalpoint/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    fraction(Rest, Stack, Callbacks, Opts, [?decimalpoint] ++ Acc);
+zero(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_whitespace(S) ->
+    maybe_done(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+zero(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts), Acc) ->
+    maybe_comment(Rest, fun(Resume) -> zero(Resume, Stack, Callbacks, Opts, Acc) end);
+zero(<<>>, [], Callbacks, Opts, Acc) ->
+    {fold(end_of_stream, fold({number, lists:reverse(Acc)}, Callbacks)), 
+        fun(Stream) -> zero(Stream, [], Callbacks, Opts, Acc) end};
+zero(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> zero(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+integer(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_nonzero(S) ->
+    integer(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
+integer(<<?end_object/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_object, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+integer(<<?end_array/?encoding, Rest/binary>>, [array|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_array, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+integer(<<?comma/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    key(Rest, [key|Stack], fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+integer(<<?comma/?encoding, Rest/binary>>, [array|_] = Stack, Callbacks, Opts, Acc) ->
+    value(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+integer(<<?decimalpoint/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    fraction(Rest, Stack, Callbacks, Opts, [?decimalpoint] ++ Acc);
+integer(<<?zero/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    integer(Rest, Stack, Callbacks, Opts, [?zero] ++ Acc);
+integer(<<$e/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    e(Rest, Stack, Callbacks, Opts, "e" ++ Acc);
+integer(<<$E/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    e(Rest, Stack, Callbacks, Opts, "e" ++ Acc);
+integer(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_whitespace(S) ->
+    maybe_done(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+integer(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts), Acc) ->
+    maybe_comment(Rest, fun(Resume) -> integer(Resume, Stack, Callbacks, Opts, Acc) end);
+integer(<<>>, [], Callbacks, Opts, Acc) ->
+    {fold(end_of_stream, fold({number, lists:reverse(Acc)}, Callbacks)), 
+        fun(Stream) -> integer(Stream, [], Callbacks, Opts, Acc) end};
+integer(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> integer(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+fraction(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_nonzero(S) ->
+    fraction(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
+fraction(<<?end_object/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_object, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+fraction(<<?end_array/?encoding, Rest/binary>>, [array|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_array, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+fraction(<<?comma/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    key(Rest, [key|Stack], fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+fraction(<<?comma/?encoding, Rest/binary>>, [array|_] = Stack, Callbacks, Opts, Acc) ->
+    value(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+fraction(<<?zero/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    fraction(Rest, Stack, Callbacks, Opts, [?zero] ++ Acc);
+fraction(<<$e/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    e(Rest, Stack, Callbacks, Opts, "e" ++ Acc);
+fraction(<<$E/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    e(Rest, Stack, Callbacks, Opts, "e" ++ Acc);
+fraction(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_whitespace(S) ->
+    maybe_done(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+fraction(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts), Acc) ->
+    maybe_comment(Rest, fun(Resume) -> fraction(Resume, Stack, Callbacks, Opts, Acc) end);
+fraction(<<>>, [], Callbacks, Opts, Acc) ->
+    {fold(end_of_stream, fold({number, lists:reverse(Acc)}, Callbacks)), 
+        fun(Stream) -> fraction(Stream, [], Callbacks, Opts, Acc) end};
+fraction(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> fraction(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+e(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when S =:= ?zero; ?is_nonzero(S) ->
+    exp(Rest, Stack, Callbacks, Opts, [S] ++ Acc);   
+e(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when S =:= ?positive; S =:= ?negative ->
+    ex(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
+e(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> e(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+ex(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when S =:= ?zero; ?is_nonzero(S) ->
+    exp(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
+ex(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> ex(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+exp(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_nonzero(S) ->
+    exp(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
+exp(<<?end_object/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_object, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+exp(<<?end_array/?encoding, Rest/binary>>, [array|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_array, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+exp(<<?comma/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    key(Rest, [key|Stack], fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+exp(<<?comma/?encoding, Rest/binary>>, [array|_] = Stack, Callbacks, Opts, Acc) ->
+    value(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+exp(<<?zero/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    exp(Rest, Stack, Callbacks, Opts, [?zero] ++ Acc);
+exp(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts), Acc) ->
+    maybe_comment(Rest, fun(Resume) -> exp(Resume, Stack, Callbacks, Opts, Acc) end);
+exp(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_whitespace(S) ->
+    maybe_done(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+exp(<<>>, [], Callbacks, Opts, Acc) ->
+    {fold(end_of_stream, fold({number, lists:reverse(Acc)}, Callbacks)), 
+        fun(Stream) -> exp(Stream, [], Callbacks, Opts, Acc) end};
+exp(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> exp(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+tr(<<$r/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    tru(Rest, Stack, Callbacks, Opts);
+tr(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> tr(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+tru(<<$u/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    true(Rest, Stack, Callbacks, Opts);
+tru(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> tru(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+true(<<$e/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    maybe_done(Rest, Stack, fold({literal, true}, Callbacks), Opts);
+true(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> true(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+fa(<<$a/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    fal(Rest, Stack, Callbacks, Opts);
+fa(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> fa(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+fal(<<$l/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    fals(Rest, Stack, Callbacks, Opts);
+fal(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> fal(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+fals(<<$s/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    false(Rest, Stack, Callbacks, Opts);
+fals(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> fals(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+false(<<$e/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    maybe_done(Rest, Stack, fold({literal, false}, Callbacks), Opts);
+false(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> false(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+nu(<<$u/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    nul(Rest, Stack, Callbacks, Opts);
+nu(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> nu(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+nul(<<$l/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    null(Rest, Stack, Callbacks, Opts);
+nul(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> nul(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+null(<<$l/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    maybe_done(Rest, Stack, fold({literal, null}, Callbacks), Opts);
+null(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> null(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.    
+
+
+%% comments are c style, /* blah blah */ and are STRONGLY discouraged. any unicode
+%%   character is valid in a comment, except, obviously the */ sequence which ends
+%%   the comment. they're implemented as a closure called when the comment ends that
+%%   returns execution to the point where the comment began. comments are not 
+%%   recorded in any way, simply parsed.    
+
+maybe_comment(<<?star/?encoding, Rest/binary>>, Resume) ->
+    comment(Rest, Resume);
+maybe_comment(Bin, Resume) ->
+    {incomplete, fun(Stream) -> maybe_comment(<<Bin/binary, Stream/binary>>, Resume) end}.
+
+
+comment(<<?star/?encoding, Rest/binary>>, Resume) ->
+    maybe_comment_done(Rest, Resume);
+comment(<<_/?encoding, Rest/binary>>, Resume) ->
+    comment(Rest, Resume);
+comment(Bin, Resume) ->
+    {incomplete, fun(Stream) -> comment(<<Bin/binary, Stream/binary>>, Resume) end}.
+
+
+maybe_comment_done(<<?solidus/?encoding, Rest/binary>>, Resume) ->
+    Resume(Rest);
+maybe_comment_done(Bin, Resume) ->
+    {incomplete, fun(Stream) -> maybe_comment_done(<<Bin/binary, Stream/binary>>, Resume) end}.
\ No newline at end of file
diff --git a/src/jsx_utf16le.erl b/src/jsx_utf16le.erl
new file mode 100644
index 0000000..1be5556
--- /dev/null
+++ b/src/jsx_utf16le.erl
@@ -0,0 +1,476 @@
+%% The MIT License
+
+%% Copyright (c) 2010 Alisdair Sullivan <alisdairsullivan@yahoo.ca>
+
+%% Permission is hereby granted, free of charge, to any person obtaining a copy
+%% of this software and associated documentation files (the "Software"), to deal
+%% in the Software without restriction, including without limitation the rights
+%% to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+%% copies of the Software, and to permit persons to whom the Software is
+%% furnished to do so, subject to the following conditions:
+
+%% The above copyright notice and this permission notice shall be included in
+%% all copies or substantial portions of the Software.
+
+%% THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+%% IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+%% FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+%% AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+%% LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+%% OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+%% THE SOFTWARE.
+
+-module(jsx_utf16le).
+-author("alisdairsullivan@yahoo.ca").
+
+-include("jsx_common.hrl").
+
+-export([start/4]).
+
+-define(encoding, utf16-little).
+
+
+%% callbacks to our handler are roughly equivalent to a fold over the events, incremental
+%%   rather than all at once.    
+
+fold(end_of_stream, {F, State}) ->
+    F(end_of_stream, State);
+fold(Event, {F, State}) when is_function(F) ->
+    {F, F(Event, State)}.
+
+
+%% this code is mostly autogenerated and mostly ugly. apologies. for more insight on
+%%   Callbacks or Opts, see the comments accompanying decoder/2 (in jsx.erl). Stack 
+%%   is a stack of flags used to track depth and to keep track of whether we are 
+%%   returning from a value or a key inside objects. all pops, peeks and pushes are 
+%%   inlined. the code that handles naked values and comments is not optimized by the 
+%%   compiler for efficient matching, but you shouldn't be using naked values or comments 
+%%   anyways, they are horrible and contrary to the spec.
+
+start(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) -> 
+    start(Rest, Stack, Callbacks, Opts);
+start(<<?start_object/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    object(Rest, [key|Stack], fold(start_object, Callbacks), Opts);
+start(<<?start_array/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    array(Rest, [array|Stack], fold(start_array, Callbacks), Opts);
+start(<<?quote/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    string(Rest, Stack, Callbacks, Opts, []);
+start(<<$t/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    tr(Rest, Stack, Callbacks, Opts);
+start(<<$f/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    fa(Rest, Stack, Callbacks, Opts);
+start(<<$n/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    nu(Rest, Stack, Callbacks, Opts);
+start(<<?negative/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    negative(Rest, Stack, Callbacks, Opts, "-");
+start(<<?zero/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    zero(Rest, Stack, Callbacks, Opts, "0");
+start(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_nonzero(S) ->
+    integer(Rest, Stack, Callbacks, Opts, [S]);
+start(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
+    maybe_comment(Rest, fun(Resume) -> start(Resume, Stack, Callbacks, Opts) end);
+start(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> start(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+maybe_done(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) ->
+    maybe_done(Rest, Stack, Callbacks, Opts);
+maybe_done(<<?end_object/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts) ->
+    maybe_done(Rest, Stack, fold(end_object, Callbacks), Opts);
+maybe_done(<<?end_array/?encoding, Rest/binary>>, [array|Stack], Callbacks, Opts) ->
+    maybe_done(Rest, Stack, fold(end_array, Callbacks), Opts);
+maybe_done(<<?comma/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts) ->
+    key(Rest, [key|Stack], Callbacks, Opts);
+maybe_done(<<?comma/?encoding, Rest/binary>>, [array|_] = Stack, Callbacks, Opts) ->
+    value(Rest, Stack, Callbacks, Opts);
+maybe_done(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
+    maybe_comment(Rest, fun(Resume) -> maybe_done(Resume, Stack, Callbacks, Opts) end);
+maybe_done(<<>>, [], Callbacks, Opts) ->
+    {fold(end_of_stream, Callbacks), fun(Stream) -> maybe_done(Stream, [], Callbacks, Opts) end};
+maybe_done(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> maybe_done(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+object(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) ->
+    object(Rest, Stack, Callbacks, Opts);
+object(<<?quote/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    string(Rest, Stack, Callbacks, Opts, []);
+object(<<?end_object/?encoding, Rest/binary>>, [key|Stack], Callbacks, Opts) ->
+    maybe_done(Rest, Stack, fold(end_object, Callbacks), Opts);
+object(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
+    maybe_comment(Rest, fun(Resume) -> object(Resume, Stack, Callbacks, Opts) end);
+object(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> object(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+array(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) -> 
+    array(Rest, Stack, Callbacks, Opts);       
+array(<<?quote/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    string(Rest, Stack, Callbacks, Opts, []);
+array(<<$t/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    tr(Rest, Stack, Callbacks, Opts);
+array(<<$f/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    fa(Rest, Stack, Callbacks, Opts);
+array(<<$n/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    nu(Rest, Stack, Callbacks, Opts);
+array(<<?negative/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    negative(Rest, Stack, Callbacks, Opts, "-");
+array(<<?zero/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    zero(Rest, Stack, Callbacks, Opts, "0");
+array(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_nonzero(S) ->
+    integer(Rest, Stack, Callbacks, Opts, [S]);
+array(<<?start_object/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    object(Rest, [key|Stack], fold(start_object, Callbacks), Opts);
+array(<<?start_array/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    array(Rest, [array|Stack], fold(start_array, Callbacks), Opts);
+array(<<?end_array/?encoding, Rest/binary>>, [array|Stack], Callbacks, Opts) ->
+    maybe_done(Rest, Stack, fold(end_array, Callbacks), Opts);
+array(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
+    maybe_comment(Rest, fun(Resume) -> array(Resume, Stack, Callbacks, Opts) end);
+array(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> array(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.  
+
+
+value(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) -> 
+    value(Rest, Stack, Callbacks, Opts);
+value(<<?quote/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    string(Rest, Stack, Callbacks, Opts, []);
+value(<<$t/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    tr(Rest, Stack, Callbacks, Opts);
+value(<<$f/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    fa(Rest, Stack, Callbacks, Opts);
+value(<<$n/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    nu(Rest, Stack, Callbacks, Opts);
+value(<<?negative/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    negative(Rest, Stack, Callbacks, Opts, "-");
+value(<<?zero/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    zero(Rest, Stack, Callbacks, Opts, "0");
+value(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_nonzero(S) ->
+    integer(Rest, Stack, Callbacks, Opts, [S]);
+value(<<?start_object/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    object(Rest, [key|Stack], fold(start_object, Callbacks), Opts);
+value(<<?start_array/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    array(Rest, [array|Stack], fold(start_array, Callbacks), Opts);
+value(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
+    maybe_comment(Rest, fun(Resume) -> value(Resume, Stack, Callbacks, Opts) end);
+value(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> value(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+colon(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) ->
+    colon(Rest, Stack, Callbacks, Opts);
+colon(<<?colon/?encoding, Rest/binary>>, [key|Stack], Callbacks, Opts) ->
+    value(Rest, [object|Stack], Callbacks, Opts);
+colon(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
+    maybe_comment(Rest, fun(Resume) -> colon(Resume, Stack, Callbacks, Opts) end);
+colon(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> colon(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+key(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) ->
+    key(Rest, Stack, Callbacks, Opts);        
+key(<<?quote/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    string(Rest, Stack, Callbacks, Opts, []);
+key(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
+    maybe_comment(Rest, fun(Resume) -> key(Resume, Stack, Callbacks, Opts) end);
+key(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> key(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+%% string has an additional parameter, an accumulator (Acc) used to hold the intermediate
+%%   representation of the string being parsed. using a list of integers representing
+%%   unicode codepoints is faster than constructing binaries, many of which will be
+%%   converted back to lists by the user anyways.
+
+%% the clause starting with Bin is necessary for cases where a stream is broken at a
+%%   point where it contains only a partial utf-8 sequence.
+
+string(<<?quote/?encoding, Rest/binary>>, [key|_] = Stack, Callbacks, Opts, Acc) ->
+    colon(Rest, Stack, fold({key, lists:reverse(Acc)}, Callbacks), Opts);
+string(<<?quote/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold({string, lists:reverse(Acc)}, Callbacks), Opts);
+string(<<?rsolidus/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    escape(Rest, Stack, Callbacks, Opts, Acc);   
+string(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_noncontrol(S) ->
+    string(Rest, Stack, Callbacks, Opts, [S] ++ Acc);   
+string(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> string(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+%% only thing to note here is the additional accumulator passed to escaped_unicode used
+%%   to hold the codepoint sequence. unescessary, but nicer than using the string 
+%%   accumulator. 
+
+escape(<<$b/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    string(Rest, Stack, Callbacks, Opts, "\b" ++ Acc);
+escape(<<$f/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    string(Rest, Stack, Callbacks, Opts, "\f" ++ Acc);
+escape(<<$n/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    string(Rest, Stack, Callbacks, Opts, "\n" ++ Acc);
+escape(<<$r/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    string(Rest, Stack, Callbacks, Opts, "\r" ++ Acc);
+escape(<<$t/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    string(Rest, Stack, Callbacks, Opts, "\t" ++ Acc);
+escape(<<$u/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    escaped_unicode(Rest, Stack, Callbacks, Opts, Acc, []);      
+escape(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) 
+        when S =:= ?quote; S =:= ?solidus; S =:= ?rsolidus ->
+    string(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
+escape(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> escape(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+%% this code is ugly and unfortunate, but so is json's handling of escaped unicode
+%%   codepoint sequences. if the ascii option is present, the sequence is converted
+%%   to a codepoint and inserted into the string if it represents an ascii value. if 
+%%   the codepoint option is present the sequence is converted and inserted as long
+%%   as it represents a valid unicode codepoint. this means non-characters 
+%%   representable in 16 bits are not converted (the utf16 surrogates and the two
+%%   special non-characters). any other option and no conversion is done.
+
+escaped_unicode(<<D/?encoding, Rest/binary>>, 
+        Stack, 
+        Callbacks, 
+        ?escaped_unicode_to_ascii(Opts), 
+        String, 
+        [C, B, A]) 
+            when ?is_hex(D) ->
+    case erlang:list_to_integer([A, B, C, D], 16) of
+        X when X < 128 ->
+            string(Rest, Stack, Callbacks, Opts, [X] ++ String)
+        ; _ ->
+            string(Rest, Stack, Callbacks, Opts, [D, C, B, A, $u, ?rsolidus] ++ String)
+    end;
+escaped_unicode(<<D/?encoding, Rest/binary>>, 
+        Stack, 
+        Callbacks, 
+        ?escaped_unicode_to_codepoint(Opts), 
+        String, 
+        [C, B, A]) 
+            when ?is_hex(D) ->
+    case erlang:list_to_integer([A, B, C, D], 16) of
+        X when X < 16#d800; X > 16#dfff, X < 16#fffe ->
+            string(Rest, Stack, Callbacks, Opts, [X] ++ String)
+        ; _ ->
+            string(Rest, Stack, Callbacks, Opts, [D, C, B, A, $u, ?rsolidus] ++ String)
+    end;
+escaped_unicode(<<D/?encoding, Rest/binary>>, Stack, Callbacks, Opts, String, [C, B, A]) when ?is_hex(D) ->
+    string(Rest, Stack, Callbacks, Opts, [D, C, B, A, $u, ?rsolidus] ++ String);
+escaped_unicode(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, String, Acc) when ?is_hex(S) ->
+    escaped_unicode(Rest, Stack, Callbacks, Opts, String, [S] ++ Acc);
+escaped_unicode(Bin, Stack, Callbacks, Opts, String, Acc) ->
+    {incomplete, fun(Stream) -> escaped_unicode(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, String, Acc) end}.
+
+
+%% like strings, numbers are collected in an intermediate accumulator before
+%%   being emitted to the callback handler. no processing of numbers is done in
+%%   process, it's left for the user, though there are convenience functions to
+%%   convert them into erlang floats/integers in jsx_utils.erl.
+
+%% TODO: actually write that jsx_utils.erl module mentioned above...
+
+negative(<<$0/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    zero(Rest, Stack, Callbacks, Opts, "0" ++ Acc);
+negative(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_nonzero(S) ->
+    integer(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
+negative(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> negative(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+zero(<<?end_object/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_object, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+zero(<<?end_array/?encoding, Rest/binary>>, [array|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_array, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+zero(<<?comma/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    key(Rest, [key|Stack], fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+zero(<<?comma/?encoding, Rest/binary>>, [array|_] = Stack, Callbacks, Opts, Acc) ->
+    value(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+zero(<<?decimalpoint/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    fraction(Rest, Stack, Callbacks, Opts, [?decimalpoint] ++ Acc);
+zero(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_whitespace(S) ->
+    maybe_done(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+zero(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts), Acc) ->
+    maybe_comment(Rest, fun(Resume) -> zero(Resume, Stack, Callbacks, Opts, Acc) end);
+zero(<<>>, [], Callbacks, Opts, Acc) ->
+    {fold(end_of_stream, fold({number, lists:reverse(Acc)}, Callbacks)), 
+        fun(Stream) -> zero(Stream, [], Callbacks, Opts, Acc) end};
+zero(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> zero(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+integer(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_nonzero(S) ->
+    integer(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
+integer(<<?end_object/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_object, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+integer(<<?end_array/?encoding, Rest/binary>>, [array|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_array, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+integer(<<?comma/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    key(Rest, [key|Stack], fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+integer(<<?comma/?encoding, Rest/binary>>, [array|_] = Stack, Callbacks, Opts, Acc) ->
+    value(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+integer(<<?decimalpoint/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    fraction(Rest, Stack, Callbacks, Opts, [?decimalpoint] ++ Acc);
+integer(<<?zero/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    integer(Rest, Stack, Callbacks, Opts, [?zero] ++ Acc);
+integer(<<$e/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    e(Rest, Stack, Callbacks, Opts, "e" ++ Acc);
+integer(<<$E/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    e(Rest, Stack, Callbacks, Opts, "e" ++ Acc);
+integer(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_whitespace(S) ->
+    maybe_done(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+integer(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts), Acc) ->
+    maybe_comment(Rest, fun(Resume) -> integer(Resume, Stack, Callbacks, Opts, Acc) end);
+integer(<<>>, [], Callbacks, Opts, Acc) ->
+    {fold(end_of_stream, fold({number, lists:reverse(Acc)}, Callbacks)), 
+        fun(Stream) -> integer(Stream, [], Callbacks, Opts, Acc) end};
+integer(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> integer(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+fraction(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_nonzero(S) ->
+    fraction(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
+fraction(<<?end_object/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_object, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+fraction(<<?end_array/?encoding, Rest/binary>>, [array|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_array, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+fraction(<<?comma/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    key(Rest, [key|Stack], fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+fraction(<<?comma/?encoding, Rest/binary>>, [array|_] = Stack, Callbacks, Opts, Acc) ->
+    value(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+fraction(<<?zero/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    fraction(Rest, Stack, Callbacks, Opts, [?zero] ++ Acc);
+fraction(<<$e/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    e(Rest, Stack, Callbacks, Opts, "e" ++ Acc);
+fraction(<<$E/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    e(Rest, Stack, Callbacks, Opts, "e" ++ Acc);
+fraction(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_whitespace(S) ->
+    maybe_done(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+fraction(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts), Acc) ->
+    maybe_comment(Rest, fun(Resume) -> fraction(Resume, Stack, Callbacks, Opts, Acc) end);
+fraction(<<>>, [], Callbacks, Opts, Acc) ->
+    {fold(end_of_stream, fold({number, lists:reverse(Acc)}, Callbacks)), 
+        fun(Stream) -> fraction(Stream, [], Callbacks, Opts, Acc) end};
+fraction(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> fraction(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+e(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when S =:= ?zero; ?is_nonzero(S) ->
+    exp(Rest, Stack, Callbacks, Opts, [S] ++ Acc);   
+e(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when S =:= ?positive; S =:= ?negative ->
+    ex(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
+e(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> e(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+ex(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when S =:= ?zero; ?is_nonzero(S) ->
+    exp(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
+ex(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> ex(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+exp(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_nonzero(S) ->
+    exp(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
+exp(<<?end_object/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_object, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+exp(<<?end_array/?encoding, Rest/binary>>, [array|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_array, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+exp(<<?comma/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    key(Rest, [key|Stack], fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+exp(<<?comma/?encoding, Rest/binary>>, [array|_] = Stack, Callbacks, Opts, Acc) ->
+    value(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+exp(<<?zero/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    exp(Rest, Stack, Callbacks, Opts, [?zero] ++ Acc);
+exp(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts), Acc) ->
+    maybe_comment(Rest, fun(Resume) -> exp(Resume, Stack, Callbacks, Opts, Acc) end);
+exp(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_whitespace(S) ->
+    maybe_done(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+exp(<<>>, [], Callbacks, Opts, Acc) ->
+    {fold(end_of_stream, fold({number, lists:reverse(Acc)}, Callbacks)), 
+        fun(Stream) -> exp(Stream, [], Callbacks, Opts, Acc) end};
+exp(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> exp(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+tr(<<$r/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    tru(Rest, Stack, Callbacks, Opts);
+tr(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> tr(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+tru(<<$u/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    true(Rest, Stack, Callbacks, Opts);
+tru(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> tru(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+true(<<$e/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    maybe_done(Rest, Stack, fold({literal, true}, Callbacks), Opts);
+true(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> true(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+fa(<<$a/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    fal(Rest, Stack, Callbacks, Opts);
+fa(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> fa(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+fal(<<$l/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    fals(Rest, Stack, Callbacks, Opts);
+fal(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> fal(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+fals(<<$s/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    false(Rest, Stack, Callbacks, Opts);
+fals(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> fals(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+false(<<$e/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    maybe_done(Rest, Stack, fold({literal, false}, Callbacks), Opts);
+false(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> false(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+nu(<<$u/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    nul(Rest, Stack, Callbacks, Opts);
+nu(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> nu(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+nul(<<$l/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    null(Rest, Stack, Callbacks, Opts);
+nul(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> nul(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+null(<<$l/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    maybe_done(Rest, Stack, fold({literal, null}, Callbacks), Opts);
+null(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> null(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.    
+
+
+%% comments are c style, /* blah blah */ and are STRONGLY discouraged. any unicode
+%%   character is valid in a comment, except, obviously the */ sequence which ends
+%%   the comment. they're implemented as a closure called when the comment ends that
+%%   returns execution to the point where the comment began. comments are not 
+%%   recorded in any way, simply parsed.    
+
+maybe_comment(<<?star/?encoding, Rest/binary>>, Resume) ->
+    comment(Rest, Resume);
+maybe_comment(Bin, Resume) ->
+    {incomplete, fun(Stream) -> maybe_comment(<<Bin/binary, Stream/binary>>, Resume) end}.
+
+
+comment(<<?star/?encoding, Rest/binary>>, Resume) ->
+    maybe_comment_done(Rest, Resume);
+comment(<<_/?encoding, Rest/binary>>, Resume) ->
+    comment(Rest, Resume);
+comment(Bin, Resume) ->
+    {incomplete, fun(Stream) -> comment(<<Bin/binary, Stream/binary>>, Resume) end}.
+
+
+maybe_comment_done(<<?solidus/?encoding, Rest/binary>>, Resume) ->
+    Resume(Rest);
+maybe_comment_done(Bin, Resume) ->
+    {incomplete, fun(Stream) -> maybe_comment_done(<<Bin/binary, Stream/binary>>, Resume) end}.
\ No newline at end of file
diff --git a/src/jsx_utf32.erl b/src/jsx_utf32.erl
new file mode 100644
index 0000000..0a5a505
--- /dev/null
+++ b/src/jsx_utf32.erl
@@ -0,0 +1,476 @@
+%% The MIT License
+
+%% Copyright (c) 2010 Alisdair Sullivan <alisdairsullivan@yahoo.ca>
+
+%% Permission is hereby granted, free of charge, to any person obtaining a copy
+%% of this software and associated documentation files (the "Software"), to deal
+%% in the Software without restriction, including without limitation the rights
+%% to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+%% copies of the Software, and to permit persons to whom the Software is
+%% furnished to do so, subject to the following conditions:
+
+%% The above copyright notice and this permission notice shall be included in
+%% all copies or substantial portions of the Software.
+
+%% THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+%% IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+%% FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+%% AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+%% LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+%% OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+%% THE SOFTWARE.
+
+-module(jsx_utf32).
+-author("alisdairsullivan@yahoo.ca").
+
+-include("jsx_common.hrl").
+
+-export([start/4]).
+
+-define(encoding, utf32).
+
+
+%% callbacks to our handler are roughly equivalent to a fold over the events, incremental
+%%   rather than all at once.    
+
+fold(end_of_stream, {F, State}) ->
+    F(end_of_stream, State);
+fold(Event, {F, State}) when is_function(F) ->
+    {F, F(Event, State)}.
+
+
+%% this code is mostly autogenerated and mostly ugly. apologies. for more insight on
+%%   Callbacks or Opts, see the comments accompanying decoder/2 (in jsx.erl). Stack 
+%%   is a stack of flags used to track depth and to keep track of whether we are 
+%%   returning from a value or a key inside objects. all pops, peeks and pushes are 
+%%   inlined. the code that handles naked values and comments is not optimized by the 
+%%   compiler for efficient matching, but you shouldn't be using naked values or comments 
+%%   anyways, they are horrible and contrary to the spec.
+
+start(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) -> 
+    start(Rest, Stack, Callbacks, Opts);
+start(<<?start_object/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    object(Rest, [key|Stack], fold(start_object, Callbacks), Opts);
+start(<<?start_array/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    array(Rest, [array|Stack], fold(start_array, Callbacks), Opts);
+start(<<?quote/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    string(Rest, Stack, Callbacks, Opts, []);
+start(<<$t/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    tr(Rest, Stack, Callbacks, Opts);
+start(<<$f/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    fa(Rest, Stack, Callbacks, Opts);
+start(<<$n/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    nu(Rest, Stack, Callbacks, Opts);
+start(<<?negative/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    negative(Rest, Stack, Callbacks, Opts, "-");
+start(<<?zero/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    zero(Rest, Stack, Callbacks, Opts, "0");
+start(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_nonzero(S) ->
+    integer(Rest, Stack, Callbacks, Opts, [S]);
+start(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
+    maybe_comment(Rest, fun(Resume) -> start(Resume, Stack, Callbacks, Opts) end);
+start(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> start(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+maybe_done(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) ->
+    maybe_done(Rest, Stack, Callbacks, Opts);
+maybe_done(<<?end_object/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts) ->
+    maybe_done(Rest, Stack, fold(end_object, Callbacks), Opts);
+maybe_done(<<?end_array/?encoding, Rest/binary>>, [array|Stack], Callbacks, Opts) ->
+    maybe_done(Rest, Stack, fold(end_array, Callbacks), Opts);
+maybe_done(<<?comma/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts) ->
+    key(Rest, [key|Stack], Callbacks, Opts);
+maybe_done(<<?comma/?encoding, Rest/binary>>, [array|_] = Stack, Callbacks, Opts) ->
+    value(Rest, Stack, Callbacks, Opts);
+maybe_done(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
+    maybe_comment(Rest, fun(Resume) -> maybe_done(Resume, Stack, Callbacks, Opts) end);
+maybe_done(<<>>, [], Callbacks, Opts) ->
+    {fold(end_of_stream, Callbacks), fun(Stream) -> maybe_done(Stream, [], Callbacks, Opts) end};
+maybe_done(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> maybe_done(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+object(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) ->
+    object(Rest, Stack, Callbacks, Opts);
+object(<<?quote/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    string(Rest, Stack, Callbacks, Opts, []);
+object(<<?end_object/?encoding, Rest/binary>>, [key|Stack], Callbacks, Opts) ->
+    maybe_done(Rest, Stack, fold(end_object, Callbacks), Opts);
+object(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
+    maybe_comment(Rest, fun(Resume) -> object(Resume, Stack, Callbacks, Opts) end);
+object(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> object(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+array(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) -> 
+    array(Rest, Stack, Callbacks, Opts);       
+array(<<?quote/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    string(Rest, Stack, Callbacks, Opts, []);
+array(<<$t/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    tr(Rest, Stack, Callbacks, Opts);
+array(<<$f/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    fa(Rest, Stack, Callbacks, Opts);
+array(<<$n/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    nu(Rest, Stack, Callbacks, Opts);
+array(<<?negative/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    negative(Rest, Stack, Callbacks, Opts, "-");
+array(<<?zero/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    zero(Rest, Stack, Callbacks, Opts, "0");
+array(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_nonzero(S) ->
+    integer(Rest, Stack, Callbacks, Opts, [S]);
+array(<<?start_object/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    object(Rest, [key|Stack], fold(start_object, Callbacks), Opts);
+array(<<?start_array/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    array(Rest, [array|Stack], fold(start_array, Callbacks), Opts);
+array(<<?end_array/?encoding, Rest/binary>>, [array|Stack], Callbacks, Opts) ->
+    maybe_done(Rest, Stack, fold(end_array, Callbacks), Opts);
+array(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
+    maybe_comment(Rest, fun(Resume) -> array(Resume, Stack, Callbacks, Opts) end);
+array(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> array(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.  
+
+
+value(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) -> 
+    value(Rest, Stack, Callbacks, Opts);
+value(<<?quote/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    string(Rest, Stack, Callbacks, Opts, []);
+value(<<$t/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    tr(Rest, Stack, Callbacks, Opts);
+value(<<$f/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    fa(Rest, Stack, Callbacks, Opts);
+value(<<$n/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    nu(Rest, Stack, Callbacks, Opts);
+value(<<?negative/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    negative(Rest, Stack, Callbacks, Opts, "-");
+value(<<?zero/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    zero(Rest, Stack, Callbacks, Opts, "0");
+value(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_nonzero(S) ->
+    integer(Rest, Stack, Callbacks, Opts, [S]);
+value(<<?start_object/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    object(Rest, [key|Stack], fold(start_object, Callbacks), Opts);
+value(<<?start_array/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    array(Rest, [array|Stack], fold(start_array, Callbacks), Opts);
+value(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
+    maybe_comment(Rest, fun(Resume) -> value(Resume, Stack, Callbacks, Opts) end);
+value(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> value(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+colon(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) ->
+    colon(Rest, Stack, Callbacks, Opts);
+colon(<<?colon/?encoding, Rest/binary>>, [key|Stack], Callbacks, Opts) ->
+    value(Rest, [object|Stack], Callbacks, Opts);
+colon(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
+    maybe_comment(Rest, fun(Resume) -> colon(Resume, Stack, Callbacks, Opts) end);
+colon(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> colon(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+key(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) ->
+    key(Rest, Stack, Callbacks, Opts);        
+key(<<?quote/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    string(Rest, Stack, Callbacks, Opts, []);
+key(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
+    maybe_comment(Rest, fun(Resume) -> key(Resume, Stack, Callbacks, Opts) end);
+key(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> key(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+%% string has an additional parameter, an accumulator (Acc) used to hold the intermediate
+%%   representation of the string being parsed. using a list of integers representing
+%%   unicode codepoints is faster than constructing binaries, many of which will be
+%%   converted back to lists by the user anyways.
+
+%% the clause starting with Bin is necessary for cases where a stream is broken at a
+%%   point where it contains only a partial utf-8 sequence.
+
+string(<<?quote/?encoding, Rest/binary>>, [key|_] = Stack, Callbacks, Opts, Acc) ->
+    colon(Rest, Stack, fold({key, lists:reverse(Acc)}, Callbacks), Opts);
+string(<<?quote/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold({string, lists:reverse(Acc)}, Callbacks), Opts);
+string(<<?rsolidus/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    escape(Rest, Stack, Callbacks, Opts, Acc);   
+string(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_noncontrol(S) ->
+    string(Rest, Stack, Callbacks, Opts, [S] ++ Acc);   
+string(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> string(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+%% only thing to note here is the additional accumulator passed to escaped_unicode used
+%%   to hold the codepoint sequence. unescessary, but nicer than using the string 
+%%   accumulator. 
+
+escape(<<$b/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    string(Rest, Stack, Callbacks, Opts, "\b" ++ Acc);
+escape(<<$f/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    string(Rest, Stack, Callbacks, Opts, "\f" ++ Acc);
+escape(<<$n/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    string(Rest, Stack, Callbacks, Opts, "\n" ++ Acc);
+escape(<<$r/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    string(Rest, Stack, Callbacks, Opts, "\r" ++ Acc);
+escape(<<$t/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    string(Rest, Stack, Callbacks, Opts, "\t" ++ Acc);
+escape(<<$u/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    escaped_unicode(Rest, Stack, Callbacks, Opts, Acc, []);      
+escape(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) 
+        when S =:= ?quote; S =:= ?solidus; S =:= ?rsolidus ->
+    string(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
+escape(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> escape(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+%% this code is ugly and unfortunate, but so is json's handling of escaped unicode
+%%   codepoint sequences. if the ascii option is present, the sequence is converted
+%%   to a codepoint and inserted into the string if it represents an ascii value. if 
+%%   the codepoint option is present the sequence is converted and inserted as long
+%%   as it represents a valid unicode codepoint. this means non-characters 
+%%   representable in 16 bits are not converted (the utf16 surrogates and the two
+%%   special non-characters). any other option and no conversion is done.
+
+escaped_unicode(<<D/?encoding, Rest/binary>>, 
+        Stack, 
+        Callbacks, 
+        ?escaped_unicode_to_ascii(Opts), 
+        String, 
+        [C, B, A]) 
+            when ?is_hex(D) ->
+    case erlang:list_to_integer([A, B, C, D], 16) of
+        X when X < 128 ->
+            string(Rest, Stack, Callbacks, Opts, [X] ++ String)
+        ; _ ->
+            string(Rest, Stack, Callbacks, Opts, [D, C, B, A, $u, ?rsolidus] ++ String)
+    end;
+escaped_unicode(<<D/?encoding, Rest/binary>>, 
+        Stack, 
+        Callbacks, 
+        ?escaped_unicode_to_codepoint(Opts), 
+        String, 
+        [C, B, A]) 
+            when ?is_hex(D) ->
+    case erlang:list_to_integer([A, B, C, D], 16) of
+        X when X < 16#d800; X > 16#dfff, X < 16#fffe ->
+            string(Rest, Stack, Callbacks, Opts, [X] ++ String)
+        ; _ ->
+            string(Rest, Stack, Callbacks, Opts, [D, C, B, A, $u, ?rsolidus] ++ String)
+    end;
+escaped_unicode(<<D/?encoding, Rest/binary>>, Stack, Callbacks, Opts, String, [C, B, A]) when ?is_hex(D) ->
+    string(Rest, Stack, Callbacks, Opts, [D, C, B, A, $u, ?rsolidus] ++ String);
+escaped_unicode(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, String, Acc) when ?is_hex(S) ->
+    escaped_unicode(Rest, Stack, Callbacks, Opts, String, [S] ++ Acc);
+escaped_unicode(Bin, Stack, Callbacks, Opts, String, Acc) ->
+    {incomplete, fun(Stream) -> escaped_unicode(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, String, Acc) end}.
+
+
+%% like strings, numbers are collected in an intermediate accumulator before
+%%   being emitted to the callback handler. no processing of numbers is done in
+%%   process, it's left for the user, though there are convenience functions to
+%%   convert them into erlang floats/integers in jsx_utils.erl.
+
+%% TODO: actually write that jsx_utils.erl module mentioned above...
+
+negative(<<$0/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    zero(Rest, Stack, Callbacks, Opts, "0" ++ Acc);
+negative(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_nonzero(S) ->
+    integer(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
+negative(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> negative(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+zero(<<?end_object/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_object, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+zero(<<?end_array/?encoding, Rest/binary>>, [array|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_array, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+zero(<<?comma/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    key(Rest, [key|Stack], fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+zero(<<?comma/?encoding, Rest/binary>>, [array|_] = Stack, Callbacks, Opts, Acc) ->
+    value(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+zero(<<?decimalpoint/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    fraction(Rest, Stack, Callbacks, Opts, [?decimalpoint] ++ Acc);
+zero(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_whitespace(S) ->
+    maybe_done(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+zero(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts), Acc) ->
+    maybe_comment(Rest, fun(Resume) -> zero(Resume, Stack, Callbacks, Opts, Acc) end);
+zero(<<>>, [], Callbacks, Opts, Acc) ->
+    {fold(end_of_stream, fold({number, lists:reverse(Acc)}, Callbacks)), 
+        fun(Stream) -> zero(Stream, [], Callbacks, Opts, Acc) end};
+zero(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> zero(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+integer(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_nonzero(S) ->
+    integer(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
+integer(<<?end_object/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_object, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+integer(<<?end_array/?encoding, Rest/binary>>, [array|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_array, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+integer(<<?comma/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    key(Rest, [key|Stack], fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+integer(<<?comma/?encoding, Rest/binary>>, [array|_] = Stack, Callbacks, Opts, Acc) ->
+    value(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+integer(<<?decimalpoint/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    fraction(Rest, Stack, Callbacks, Opts, [?decimalpoint] ++ Acc);
+integer(<<?zero/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    integer(Rest, Stack, Callbacks, Opts, [?zero] ++ Acc);
+integer(<<$e/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    e(Rest, Stack, Callbacks, Opts, "e" ++ Acc);
+integer(<<$E/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    e(Rest, Stack, Callbacks, Opts, "e" ++ Acc);
+integer(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_whitespace(S) ->
+    maybe_done(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+integer(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts), Acc) ->
+    maybe_comment(Rest, fun(Resume) -> integer(Resume, Stack, Callbacks, Opts, Acc) end);
+integer(<<>>, [], Callbacks, Opts, Acc) ->
+    {fold(end_of_stream, fold({number, lists:reverse(Acc)}, Callbacks)), 
+        fun(Stream) -> integer(Stream, [], Callbacks, Opts, Acc) end};
+integer(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> integer(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+fraction(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_nonzero(S) ->
+    fraction(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
+fraction(<<?end_object/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_object, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+fraction(<<?end_array/?encoding, Rest/binary>>, [array|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_array, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+fraction(<<?comma/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    key(Rest, [key|Stack], fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+fraction(<<?comma/?encoding, Rest/binary>>, [array|_] = Stack, Callbacks, Opts, Acc) ->
+    value(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+fraction(<<?zero/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    fraction(Rest, Stack, Callbacks, Opts, [?zero] ++ Acc);
+fraction(<<$e/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    e(Rest, Stack, Callbacks, Opts, "e" ++ Acc);
+fraction(<<$E/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    e(Rest, Stack, Callbacks, Opts, "e" ++ Acc);
+fraction(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_whitespace(S) ->
+    maybe_done(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+fraction(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts), Acc) ->
+    maybe_comment(Rest, fun(Resume) -> fraction(Resume, Stack, Callbacks, Opts, Acc) end);
+fraction(<<>>, [], Callbacks, Opts, Acc) ->
+    {fold(end_of_stream, fold({number, lists:reverse(Acc)}, Callbacks)), 
+        fun(Stream) -> fraction(Stream, [], Callbacks, Opts, Acc) end};
+fraction(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> fraction(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+e(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when S =:= ?zero; ?is_nonzero(S) ->
+    exp(Rest, Stack, Callbacks, Opts, [S] ++ Acc);   
+e(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when S =:= ?positive; S =:= ?negative ->
+    ex(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
+e(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> e(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+ex(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when S =:= ?zero; ?is_nonzero(S) ->
+    exp(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
+ex(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> ex(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+exp(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_nonzero(S) ->
+    exp(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
+exp(<<?end_object/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_object, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+exp(<<?end_array/?encoding, Rest/binary>>, [array|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_array, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+exp(<<?comma/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    key(Rest, [key|Stack], fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+exp(<<?comma/?encoding, Rest/binary>>, [array|_] = Stack, Callbacks, Opts, Acc) ->
+    value(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+exp(<<?zero/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    exp(Rest, Stack, Callbacks, Opts, [?zero] ++ Acc);
+exp(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts), Acc) ->
+    maybe_comment(Rest, fun(Resume) -> exp(Resume, Stack, Callbacks, Opts, Acc) end);
+exp(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_whitespace(S) ->
+    maybe_done(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+exp(<<>>, [], Callbacks, Opts, Acc) ->
+    {fold(end_of_stream, fold({number, lists:reverse(Acc)}, Callbacks)), 
+        fun(Stream) -> exp(Stream, [], Callbacks, Opts, Acc) end};
+exp(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> exp(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+tr(<<$r/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    tru(Rest, Stack, Callbacks, Opts);
+tr(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> tr(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+tru(<<$u/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    true(Rest, Stack, Callbacks, Opts);
+tru(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> tru(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+true(<<$e/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    maybe_done(Rest, Stack, fold({literal, true}, Callbacks), Opts);
+true(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> true(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+fa(<<$a/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    fal(Rest, Stack, Callbacks, Opts);
+fa(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> fa(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+fal(<<$l/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    fals(Rest, Stack, Callbacks, Opts);
+fal(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> fal(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+fals(<<$s/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    false(Rest, Stack, Callbacks, Opts);
+fals(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> fals(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+false(<<$e/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    maybe_done(Rest, Stack, fold({literal, false}, Callbacks), Opts);
+false(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> false(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+nu(<<$u/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    nul(Rest, Stack, Callbacks, Opts);
+nu(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> nu(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+nul(<<$l/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    null(Rest, Stack, Callbacks, Opts);
+nul(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> nul(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+null(<<$l/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    maybe_done(Rest, Stack, fold({literal, null}, Callbacks), Opts);
+null(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> null(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.    
+
+
+%% comments are c style, /* blah blah */ and are STRONGLY discouraged. any unicode
+%%   character is valid in a comment, except, obviously the */ sequence which ends
+%%   the comment. they're implemented as a closure called when the comment ends that
+%%   returns execution to the point where the comment began. comments are not 
+%%   recorded in any way, simply parsed.    
+
+maybe_comment(<<?star/?encoding, Rest/binary>>, Resume) ->
+    comment(Rest, Resume);
+maybe_comment(Bin, Resume) ->
+    {incomplete, fun(Stream) -> maybe_comment(<<Bin/binary, Stream/binary>>, Resume) end}.
+
+
+comment(<<?star/?encoding, Rest/binary>>, Resume) ->
+    maybe_comment_done(Rest, Resume);
+comment(<<_/?encoding, Rest/binary>>, Resume) ->
+    comment(Rest, Resume);
+comment(Bin, Resume) ->
+    {incomplete, fun(Stream) -> comment(<<Bin/binary, Stream/binary>>, Resume) end}.
+
+
+maybe_comment_done(<<?solidus/?encoding, Rest/binary>>, Resume) ->
+    Resume(Rest);
+maybe_comment_done(Bin, Resume) ->
+    {incomplete, fun(Stream) -> maybe_comment_done(<<Bin/binary, Stream/binary>>, Resume) end}.
\ No newline at end of file
diff --git a/src/jsx_utf32le.erl b/src/jsx_utf32le.erl
new file mode 100644
index 0000000..505b14f
--- /dev/null
+++ b/src/jsx_utf32le.erl
@@ -0,0 +1,476 @@
+%% The MIT License
+
+%% Copyright (c) 2010 Alisdair Sullivan <alisdairsullivan@yahoo.ca>
+
+%% Permission is hereby granted, free of charge, to any person obtaining a copy
+%% of this software and associated documentation files (the "Software"), to deal
+%% in the Software without restriction, including without limitation the rights
+%% to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+%% copies of the Software, and to permit persons to whom the Software is
+%% furnished to do so, subject to the following conditions:
+
+%% The above copyright notice and this permission notice shall be included in
+%% all copies or substantial portions of the Software.
+
+%% THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+%% IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+%% FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+%% AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+%% LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+%% OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+%% THE SOFTWARE.
+
+-module(jsx_utf32le).
+-author("alisdairsullivan@yahoo.ca").
+
+-include("jsx_common.hrl").
+
+-export([start/4]).
+
+-define(encoding, utf32-little).
+
+
+%% callbacks to our handler are roughly equivalent to a fold over the events, incremental
+%%   rather than all at once.    
+
+fold(end_of_stream, {F, State}) ->
+    F(end_of_stream, State);
+fold(Event, {F, State}) when is_function(F) ->
+    {F, F(Event, State)}.
+
+
+%% this code is mostly autogenerated and mostly ugly. apologies. for more insight on
+%%   Callbacks or Opts, see the comments accompanying decoder/2 (in jsx.erl). Stack 
+%%   is a stack of flags used to track depth and to keep track of whether we are 
+%%   returning from a value or a key inside objects. all pops, peeks and pushes are 
+%%   inlined. the code that handles naked values and comments is not optimized by the 
+%%   compiler for efficient matching, but you shouldn't be using naked values or comments 
+%%   anyways, they are horrible and contrary to the spec.
+
+start(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) -> 
+    start(Rest, Stack, Callbacks, Opts);
+start(<<?start_object/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    object(Rest, [key|Stack], fold(start_object, Callbacks), Opts);
+start(<<?start_array/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    array(Rest, [array|Stack], fold(start_array, Callbacks), Opts);
+start(<<?quote/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    string(Rest, Stack, Callbacks, Opts, []);
+start(<<$t/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    tr(Rest, Stack, Callbacks, Opts);
+start(<<$f/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    fa(Rest, Stack, Callbacks, Opts);
+start(<<$n/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    nu(Rest, Stack, Callbacks, Opts);
+start(<<?negative/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    negative(Rest, Stack, Callbacks, Opts, "-");
+start(<<?zero/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    zero(Rest, Stack, Callbacks, Opts, "0");
+start(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_nonzero(S) ->
+    integer(Rest, Stack, Callbacks, Opts, [S]);
+start(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
+    maybe_comment(Rest, fun(Resume) -> start(Resume, Stack, Callbacks, Opts) end);
+start(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> start(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+maybe_done(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) ->
+    maybe_done(Rest, Stack, Callbacks, Opts);
+maybe_done(<<?end_object/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts) ->
+    maybe_done(Rest, Stack, fold(end_object, Callbacks), Opts);
+maybe_done(<<?end_array/?encoding, Rest/binary>>, [array|Stack], Callbacks, Opts) ->
+    maybe_done(Rest, Stack, fold(end_array, Callbacks), Opts);
+maybe_done(<<?comma/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts) ->
+    key(Rest, [key|Stack], Callbacks, Opts);
+maybe_done(<<?comma/?encoding, Rest/binary>>, [array|_] = Stack, Callbacks, Opts) ->
+    value(Rest, Stack, Callbacks, Opts);
+maybe_done(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
+    maybe_comment(Rest, fun(Resume) -> maybe_done(Resume, Stack, Callbacks, Opts) end);
+maybe_done(<<>>, [], Callbacks, Opts) ->
+    {fold(end_of_stream, Callbacks), fun(Stream) -> maybe_done(Stream, [], Callbacks, Opts) end};
+maybe_done(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> maybe_done(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+object(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) ->
+    object(Rest, Stack, Callbacks, Opts);
+object(<<?quote/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    string(Rest, Stack, Callbacks, Opts, []);
+object(<<?end_object/?encoding, Rest/binary>>, [key|Stack], Callbacks, Opts) ->
+    maybe_done(Rest, Stack, fold(end_object, Callbacks), Opts);
+object(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
+    maybe_comment(Rest, fun(Resume) -> object(Resume, Stack, Callbacks, Opts) end);
+object(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> object(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+array(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) -> 
+    array(Rest, Stack, Callbacks, Opts);       
+array(<<?quote/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    string(Rest, Stack, Callbacks, Opts, []);
+array(<<$t/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    tr(Rest, Stack, Callbacks, Opts);
+array(<<$f/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    fa(Rest, Stack, Callbacks, Opts);
+array(<<$n/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    nu(Rest, Stack, Callbacks, Opts);
+array(<<?negative/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    negative(Rest, Stack, Callbacks, Opts, "-");
+array(<<?zero/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    zero(Rest, Stack, Callbacks, Opts, "0");
+array(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_nonzero(S) ->
+    integer(Rest, Stack, Callbacks, Opts, [S]);
+array(<<?start_object/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    object(Rest, [key|Stack], fold(start_object, Callbacks), Opts);
+array(<<?start_array/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    array(Rest, [array|Stack], fold(start_array, Callbacks), Opts);
+array(<<?end_array/?encoding, Rest/binary>>, [array|Stack], Callbacks, Opts) ->
+    maybe_done(Rest, Stack, fold(end_array, Callbacks), Opts);
+array(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
+    maybe_comment(Rest, fun(Resume) -> array(Resume, Stack, Callbacks, Opts) end);
+array(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> array(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.  
+
+
+value(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) -> 
+    value(Rest, Stack, Callbacks, Opts);
+value(<<?quote/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    string(Rest, Stack, Callbacks, Opts, []);
+value(<<$t/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    tr(Rest, Stack, Callbacks, Opts);
+value(<<$f/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    fa(Rest, Stack, Callbacks, Opts);
+value(<<$n/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    nu(Rest, Stack, Callbacks, Opts);
+value(<<?negative/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    negative(Rest, Stack, Callbacks, Opts, "-");
+value(<<?zero/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    zero(Rest, Stack, Callbacks, Opts, "0");
+value(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_nonzero(S) ->
+    integer(Rest, Stack, Callbacks, Opts, [S]);
+value(<<?start_object/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    object(Rest, [key|Stack], fold(start_object, Callbacks), Opts);
+value(<<?start_array/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    array(Rest, [array|Stack], fold(start_array, Callbacks), Opts);
+value(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
+    maybe_comment(Rest, fun(Resume) -> value(Resume, Stack, Callbacks, Opts) end);
+value(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> value(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+colon(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) ->
+    colon(Rest, Stack, Callbacks, Opts);
+colon(<<?colon/?encoding, Rest/binary>>, [key|Stack], Callbacks, Opts) ->
+    value(Rest, [object|Stack], Callbacks, Opts);
+colon(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
+    maybe_comment(Rest, fun(Resume) -> colon(Resume, Stack, Callbacks, Opts) end);
+colon(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> colon(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+key(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) ->
+    key(Rest, Stack, Callbacks, Opts);        
+key(<<?quote/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    string(Rest, Stack, Callbacks, Opts, []);
+key(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
+    maybe_comment(Rest, fun(Resume) -> key(Resume, Stack, Callbacks, Opts) end);
+key(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> key(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+%% string has an additional parameter, an accumulator (Acc) used to hold the intermediate
+%%   representation of the string being parsed. using a list of integers representing
+%%   unicode codepoints is faster than constructing binaries, many of which will be
+%%   converted back to lists by the user anyways.
+
+%% the clause starting with Bin is necessary for cases where a stream is broken at a
+%%   point where it contains only a partial utf-8 sequence.
+
+string(<<?quote/?encoding, Rest/binary>>, [key|_] = Stack, Callbacks, Opts, Acc) ->
+    colon(Rest, Stack, fold({key, lists:reverse(Acc)}, Callbacks), Opts);
+string(<<?quote/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold({string, lists:reverse(Acc)}, Callbacks), Opts);
+string(<<?rsolidus/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    escape(Rest, Stack, Callbacks, Opts, Acc);   
+string(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_noncontrol(S) ->
+    string(Rest, Stack, Callbacks, Opts, [S] ++ Acc);   
+string(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> string(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+%% only thing to note here is the additional accumulator passed to escaped_unicode used
+%%   to hold the codepoint sequence. unescessary, but nicer than using the string 
+%%   accumulator. 
+
+escape(<<$b/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    string(Rest, Stack, Callbacks, Opts, "\b" ++ Acc);
+escape(<<$f/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    string(Rest, Stack, Callbacks, Opts, "\f" ++ Acc);
+escape(<<$n/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    string(Rest, Stack, Callbacks, Opts, "\n" ++ Acc);
+escape(<<$r/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    string(Rest, Stack, Callbacks, Opts, "\r" ++ Acc);
+escape(<<$t/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    string(Rest, Stack, Callbacks, Opts, "\t" ++ Acc);
+escape(<<$u/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    escaped_unicode(Rest, Stack, Callbacks, Opts, Acc, []);      
+escape(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) 
+        when S =:= ?quote; S =:= ?solidus; S =:= ?rsolidus ->
+    string(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
+escape(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> escape(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+%% this code is ugly and unfortunate, but so is json's handling of escaped unicode
+%%   codepoint sequences. if the ascii option is present, the sequence is converted
+%%   to a codepoint and inserted into the string if it represents an ascii value. if 
+%%   the codepoint option is present the sequence is converted and inserted as long
+%%   as it represents a valid unicode codepoint. this means non-characters 
+%%   representable in 16 bits are not converted (the utf16 surrogates and the two
+%%   special non-characters). any other option and no conversion is done.
+
+escaped_unicode(<<D/?encoding, Rest/binary>>, 
+        Stack, 
+        Callbacks, 
+        ?escaped_unicode_to_ascii(Opts), 
+        String, 
+        [C, B, A]) 
+            when ?is_hex(D) ->
+    case erlang:list_to_integer([A, B, C, D], 16) of
+        X when X < 128 ->
+            string(Rest, Stack, Callbacks, Opts, [X] ++ String)
+        ; _ ->
+            string(Rest, Stack, Callbacks, Opts, [D, C, B, A, $u, ?rsolidus] ++ String)
+    end;
+escaped_unicode(<<D/?encoding, Rest/binary>>, 
+        Stack, 
+        Callbacks, 
+        ?escaped_unicode_to_codepoint(Opts), 
+        String, 
+        [C, B, A]) 
+            when ?is_hex(D) ->
+    case erlang:list_to_integer([A, B, C, D], 16) of
+        X when X < 16#d800; X > 16#dfff, X < 16#fffe ->
+            string(Rest, Stack, Callbacks, Opts, [X] ++ String)
+        ; _ ->
+            string(Rest, Stack, Callbacks, Opts, [D, C, B, A, $u, ?rsolidus] ++ String)
+    end;
+escaped_unicode(<<D/?encoding, Rest/binary>>, Stack, Callbacks, Opts, String, [C, B, A]) when ?is_hex(D) ->
+    string(Rest, Stack, Callbacks, Opts, [D, C, B, A, $u, ?rsolidus] ++ String);
+escaped_unicode(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, String, Acc) when ?is_hex(S) ->
+    escaped_unicode(Rest, Stack, Callbacks, Opts, String, [S] ++ Acc);
+escaped_unicode(Bin, Stack, Callbacks, Opts, String, Acc) ->
+    {incomplete, fun(Stream) -> escaped_unicode(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, String, Acc) end}.
+
+
+%% like strings, numbers are collected in an intermediate accumulator before
+%%   being emitted to the callback handler. no processing of numbers is done in
+%%   process, it's left for the user, though there are convenience functions to
+%%   convert them into erlang floats/integers in jsx_utils.erl.
+
+%% TODO: actually write that jsx_utils.erl module mentioned above...
+
+negative(<<$0/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    zero(Rest, Stack, Callbacks, Opts, "0" ++ Acc);
+negative(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_nonzero(S) ->
+    integer(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
+negative(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> negative(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+zero(<<?end_object/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_object, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+zero(<<?end_array/?encoding, Rest/binary>>, [array|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_array, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+zero(<<?comma/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    key(Rest, [key|Stack], fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+zero(<<?comma/?encoding, Rest/binary>>, [array|_] = Stack, Callbacks, Opts, Acc) ->
+    value(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+zero(<<?decimalpoint/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    fraction(Rest, Stack, Callbacks, Opts, [?decimalpoint] ++ Acc);
+zero(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_whitespace(S) ->
+    maybe_done(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+zero(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts), Acc) ->
+    maybe_comment(Rest, fun(Resume) -> zero(Resume, Stack, Callbacks, Opts, Acc) end);
+zero(<<>>, [], Callbacks, Opts, Acc) ->
+    {fold(end_of_stream, fold({number, lists:reverse(Acc)}, Callbacks)), 
+        fun(Stream) -> zero(Stream, [], Callbacks, Opts, Acc) end};
+zero(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> zero(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+integer(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_nonzero(S) ->
+    integer(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
+integer(<<?end_object/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_object, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+integer(<<?end_array/?encoding, Rest/binary>>, [array|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_array, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+integer(<<?comma/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    key(Rest, [key|Stack], fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+integer(<<?comma/?encoding, Rest/binary>>, [array|_] = Stack, Callbacks, Opts, Acc) ->
+    value(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+integer(<<?decimalpoint/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    fraction(Rest, Stack, Callbacks, Opts, [?decimalpoint] ++ Acc);
+integer(<<?zero/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    integer(Rest, Stack, Callbacks, Opts, [?zero] ++ Acc);
+integer(<<$e/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    e(Rest, Stack, Callbacks, Opts, "e" ++ Acc);
+integer(<<$E/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    e(Rest, Stack, Callbacks, Opts, "e" ++ Acc);
+integer(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_whitespace(S) ->
+    maybe_done(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+integer(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts), Acc) ->
+    maybe_comment(Rest, fun(Resume) -> integer(Resume, Stack, Callbacks, Opts, Acc) end);
+integer(<<>>, [], Callbacks, Opts, Acc) ->
+    {fold(end_of_stream, fold({number, lists:reverse(Acc)}, Callbacks)), 
+        fun(Stream) -> integer(Stream, [], Callbacks, Opts, Acc) end};
+integer(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> integer(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+fraction(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_nonzero(S) ->
+    fraction(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
+fraction(<<?end_object/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_object, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+fraction(<<?end_array/?encoding, Rest/binary>>, [array|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_array, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+fraction(<<?comma/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    key(Rest, [key|Stack], fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+fraction(<<?comma/?encoding, Rest/binary>>, [array|_] = Stack, Callbacks, Opts, Acc) ->
+    value(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+fraction(<<?zero/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    fraction(Rest, Stack, Callbacks, Opts, [?zero] ++ Acc);
+fraction(<<$e/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    e(Rest, Stack, Callbacks, Opts, "e" ++ Acc);
+fraction(<<$E/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    e(Rest, Stack, Callbacks, Opts, "e" ++ Acc);
+fraction(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_whitespace(S) ->
+    maybe_done(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+fraction(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts), Acc) ->
+    maybe_comment(Rest, fun(Resume) -> fraction(Resume, Stack, Callbacks, Opts, Acc) end);
+fraction(<<>>, [], Callbacks, Opts, Acc) ->
+    {fold(end_of_stream, fold({number, lists:reverse(Acc)}, Callbacks)), 
+        fun(Stream) -> fraction(Stream, [], Callbacks, Opts, Acc) end};
+fraction(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> fraction(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+e(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when S =:= ?zero; ?is_nonzero(S) ->
+    exp(Rest, Stack, Callbacks, Opts, [S] ++ Acc);   
+e(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when S =:= ?positive; S =:= ?negative ->
+    ex(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
+e(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> e(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+ex(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when S =:= ?zero; ?is_nonzero(S) ->
+    exp(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
+ex(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> ex(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+exp(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_nonzero(S) ->
+    exp(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
+exp(<<?end_object/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_object, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+exp(<<?end_array/?encoding, Rest/binary>>, [array|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_array, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+exp(<<?comma/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    key(Rest, [key|Stack], fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+exp(<<?comma/?encoding, Rest/binary>>, [array|_] = Stack, Callbacks, Opts, Acc) ->
+    value(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+exp(<<?zero/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    exp(Rest, Stack, Callbacks, Opts, [?zero] ++ Acc);
+exp(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts), Acc) ->
+    maybe_comment(Rest, fun(Resume) -> exp(Resume, Stack, Callbacks, Opts, Acc) end);
+exp(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_whitespace(S) ->
+    maybe_done(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+exp(<<>>, [], Callbacks, Opts, Acc) ->
+    {fold(end_of_stream, fold({number, lists:reverse(Acc)}, Callbacks)), 
+        fun(Stream) -> exp(Stream, [], Callbacks, Opts, Acc) end};
+exp(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> exp(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+tr(<<$r/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    tru(Rest, Stack, Callbacks, Opts);
+tr(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> tr(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+tru(<<$u/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    true(Rest, Stack, Callbacks, Opts);
+tru(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> tru(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+true(<<$e/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    maybe_done(Rest, Stack, fold({literal, true}, Callbacks), Opts);
+true(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> true(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+fa(<<$a/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    fal(Rest, Stack, Callbacks, Opts);
+fa(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> fa(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+fal(<<$l/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    fals(Rest, Stack, Callbacks, Opts);
+fal(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> fal(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+fals(<<$s/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    false(Rest, Stack, Callbacks, Opts);
+fals(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> fals(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+false(<<$e/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    maybe_done(Rest, Stack, fold({literal, false}, Callbacks), Opts);
+false(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> false(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+nu(<<$u/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    nul(Rest, Stack, Callbacks, Opts);
+nu(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> nu(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+nul(<<$l/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    null(Rest, Stack, Callbacks, Opts);
+nul(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> nul(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+null(<<$l/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    maybe_done(Rest, Stack, fold({literal, null}, Callbacks), Opts);
+null(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> null(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.    
+
+
+%% comments are c style, /* blah blah */ and are STRONGLY discouraged. any unicode
+%%   character is valid in a comment, except, obviously the */ sequence which ends
+%%   the comment. they're implemented as a closure called when the comment ends that
+%%   returns execution to the point where the comment began. comments are not 
+%%   recorded in any way, simply parsed.    
+
+maybe_comment(<<?star/?encoding, Rest/binary>>, Resume) ->
+    comment(Rest, Resume);
+maybe_comment(Bin, Resume) ->
+    {incomplete, fun(Stream) -> maybe_comment(<<Bin/binary, Stream/binary>>, Resume) end}.
+
+
+comment(<<?star/?encoding, Rest/binary>>, Resume) ->
+    maybe_comment_done(Rest, Resume);
+comment(<<_/?encoding, Rest/binary>>, Resume) ->
+    comment(Rest, Resume);
+comment(Bin, Resume) ->
+    {incomplete, fun(Stream) -> comment(<<Bin/binary, Stream/binary>>, Resume) end}.
+
+
+maybe_comment_done(<<?solidus/?encoding, Rest/binary>>, Resume) ->
+    Resume(Rest);
+maybe_comment_done(Bin, Resume) ->
+    {incomplete, fun(Stream) -> maybe_comment_done(<<Bin/binary, Stream/binary>>, Resume) end}.
\ No newline at end of file
diff --git a/src/jsx_utf8.erl b/src/jsx_utf8.erl
new file mode 100644
index 0000000..92a9c61
--- /dev/null
+++ b/src/jsx_utf8.erl
@@ -0,0 +1,476 @@
+%% The MIT License
+
+%% Copyright (c) 2010 Alisdair Sullivan <alisdairsullivan@yahoo.ca>
+
+%% Permission is hereby granted, free of charge, to any person obtaining a copy
+%% of this software and associated documentation files (the "Software"), to deal
+%% in the Software without restriction, including without limitation the rights
+%% to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+%% copies of the Software, and to permit persons to whom the Software is
+%% furnished to do so, subject to the following conditions:
+
+%% The above copyright notice and this permission notice shall be included in
+%% all copies or substantial portions of the Software.
+
+%% THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+%% IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+%% FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+%% AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+%% LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+%% OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+%% THE SOFTWARE.
+
+-module(jsx_utf8).
+-author("alisdairsullivan@yahoo.ca").
+
+-include("jsx_common.hrl").
+
+-export([start/4]).
+
+-define(encoding, utf8).
+
+
+%% callbacks to our handler are roughly equivalent to a fold over the events, incremental
+%%   rather than all at once.    
+
+fold(end_of_stream, {F, State}) ->
+    F(end_of_stream, State);
+fold(Event, {F, State}) when is_function(F) ->
+    {F, F(Event, State)}.
+
+
+%% this code is mostly autogenerated and mostly ugly. apologies. for more insight on
+%%   Callbacks or Opts, see the comments accompanying decoder/2 (in jsx.erl). Stack 
+%%   is a stack of flags used to track depth and to keep track of whether we are 
+%%   returning from a value or a key inside objects. all pops, peeks and pushes are 
+%%   inlined. the code that handles naked values and comments is not optimized by the 
+%%   compiler for efficient matching, but you shouldn't be using naked values or comments 
+%%   anyways, they are horrible and contrary to the spec.
+
+start(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) -> 
+    start(Rest, Stack, Callbacks, Opts);
+start(<<?start_object/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    object(Rest, [key|Stack], fold(start_object, Callbacks), Opts);
+start(<<?start_array/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    array(Rest, [array|Stack], fold(start_array, Callbacks), Opts);
+start(<<?quote/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    string(Rest, Stack, Callbacks, Opts, []);
+start(<<$t/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    tr(Rest, Stack, Callbacks, Opts);
+start(<<$f/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    fa(Rest, Stack, Callbacks, Opts);
+start(<<$n/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    nu(Rest, Stack, Callbacks, Opts);
+start(<<?negative/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    negative(Rest, Stack, Callbacks, Opts, "-");
+start(<<?zero/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    zero(Rest, Stack, Callbacks, Opts, "0");
+start(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_nonzero(S) ->
+    integer(Rest, Stack, Callbacks, Opts, [S]);
+start(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
+    maybe_comment(Rest, fun(Resume) -> start(Resume, Stack, Callbacks, Opts) end);
+start(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> start(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+maybe_done(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) ->
+    maybe_done(Rest, Stack, Callbacks, Opts);
+maybe_done(<<?end_object/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts) ->
+    maybe_done(Rest, Stack, fold(end_object, Callbacks), Opts);
+maybe_done(<<?end_array/?encoding, Rest/binary>>, [array|Stack], Callbacks, Opts) ->
+    maybe_done(Rest, Stack, fold(end_array, Callbacks), Opts);
+maybe_done(<<?comma/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts) ->
+    key(Rest, [key|Stack], Callbacks, Opts);
+maybe_done(<<?comma/?encoding, Rest/binary>>, [array|_] = Stack, Callbacks, Opts) ->
+    value(Rest, Stack, Callbacks, Opts);
+maybe_done(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
+    maybe_comment(Rest, fun(Resume) -> maybe_done(Resume, Stack, Callbacks, Opts) end);
+maybe_done(<<>>, [], Callbacks, Opts) ->
+    {fold(end_of_stream, Callbacks), fun(Stream) -> maybe_done(Stream, [], Callbacks, Opts) end};
+maybe_done(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> maybe_done(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+object(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) ->
+    object(Rest, Stack, Callbacks, Opts);
+object(<<?quote/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    string(Rest, Stack, Callbacks, Opts, []);
+object(<<?end_object/?encoding, Rest/binary>>, [key|Stack], Callbacks, Opts) ->
+    maybe_done(Rest, Stack, fold(end_object, Callbacks), Opts);
+object(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
+    maybe_comment(Rest, fun(Resume) -> object(Resume, Stack, Callbacks, Opts) end);
+object(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> object(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+array(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) -> 
+    array(Rest, Stack, Callbacks, Opts);       
+array(<<?quote/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    string(Rest, Stack, Callbacks, Opts, []);
+array(<<$t/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    tr(Rest, Stack, Callbacks, Opts);
+array(<<$f/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    fa(Rest, Stack, Callbacks, Opts);
+array(<<$n/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    nu(Rest, Stack, Callbacks, Opts);
+array(<<?negative/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    negative(Rest, Stack, Callbacks, Opts, "-");
+array(<<?zero/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    zero(Rest, Stack, Callbacks, Opts, "0");
+array(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_nonzero(S) ->
+    integer(Rest, Stack, Callbacks, Opts, [S]);
+array(<<?start_object/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    object(Rest, [key|Stack], fold(start_object, Callbacks), Opts);
+array(<<?start_array/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    array(Rest, [array|Stack], fold(start_array, Callbacks), Opts);
+array(<<?end_array/?encoding, Rest/binary>>, [array|Stack], Callbacks, Opts) ->
+    maybe_done(Rest, Stack, fold(end_array, Callbacks), Opts);
+array(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
+    maybe_comment(Rest, fun(Resume) -> array(Resume, Stack, Callbacks, Opts) end);
+array(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> array(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.  
+
+
+value(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) -> 
+    value(Rest, Stack, Callbacks, Opts);
+value(<<?quote/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    string(Rest, Stack, Callbacks, Opts, []);
+value(<<$t/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    tr(Rest, Stack, Callbacks, Opts);
+value(<<$f/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    fa(Rest, Stack, Callbacks, Opts);
+value(<<$n/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    nu(Rest, Stack, Callbacks, Opts);
+value(<<?negative/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    negative(Rest, Stack, Callbacks, Opts, "-");
+value(<<?zero/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    zero(Rest, Stack, Callbacks, Opts, "0");
+value(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_nonzero(S) ->
+    integer(Rest, Stack, Callbacks, Opts, [S]);
+value(<<?start_object/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    object(Rest, [key|Stack], fold(start_object, Callbacks), Opts);
+value(<<?start_array/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    array(Rest, [array|Stack], fold(start_array, Callbacks), Opts);
+value(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
+    maybe_comment(Rest, fun(Resume) -> value(Resume, Stack, Callbacks, Opts) end);
+value(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> value(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+colon(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) ->
+    colon(Rest, Stack, Callbacks, Opts);
+colon(<<?colon/?encoding, Rest/binary>>, [key|Stack], Callbacks, Opts) ->
+    value(Rest, [object|Stack], Callbacks, Opts);
+colon(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
+    maybe_comment(Rest, fun(Resume) -> colon(Resume, Stack, Callbacks, Opts) end);
+colon(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> colon(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+key(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts) when ?is_whitespace(S) ->
+    key(Rest, Stack, Callbacks, Opts);        
+key(<<?quote/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    string(Rest, Stack, Callbacks, Opts, []);
+key(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts)) ->
+    maybe_comment(Rest, fun(Resume) -> key(Resume, Stack, Callbacks, Opts) end);
+key(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> key(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+%% string has an additional parameter, an accumulator (Acc) used to hold the intermediate
+%%   representation of the string being parsed. using a list of integers representing
+%%   unicode codepoints is faster than constructing binaries, many of which will be
+%%   converted back to lists by the user anyways.
+
+%% the clause starting with Bin is necessary for cases where a stream is broken at a
+%%   point where it contains only a partial utf-8 sequence.
+
+string(<<?quote/?encoding, Rest/binary>>, [key|_] = Stack, Callbacks, Opts, Acc) ->
+    colon(Rest, Stack, fold({key, lists:reverse(Acc)}, Callbacks), Opts);
+string(<<?quote/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold({string, lists:reverse(Acc)}, Callbacks), Opts);
+string(<<?rsolidus/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    escape(Rest, Stack, Callbacks, Opts, Acc);   
+string(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_noncontrol(S) ->
+    string(Rest, Stack, Callbacks, Opts, [S] ++ Acc);   
+string(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> string(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+%% only thing to note here is the additional accumulator passed to escaped_unicode used
+%%   to hold the codepoint sequence. unescessary, but nicer than using the string 
+%%   accumulator. 
+
+escape(<<$b/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    string(Rest, Stack, Callbacks, Opts, "\b" ++ Acc);
+escape(<<$f/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    string(Rest, Stack, Callbacks, Opts, "\f" ++ Acc);
+escape(<<$n/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    string(Rest, Stack, Callbacks, Opts, "\n" ++ Acc);
+escape(<<$r/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    string(Rest, Stack, Callbacks, Opts, "\r" ++ Acc);
+escape(<<$t/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    string(Rest, Stack, Callbacks, Opts, "\t" ++ Acc);
+escape(<<$u/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    escaped_unicode(Rest, Stack, Callbacks, Opts, Acc, []);      
+escape(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) 
+        when S =:= ?quote; S =:= ?solidus; S =:= ?rsolidus ->
+    string(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
+escape(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> escape(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+%% this code is ugly and unfortunate, but so is json's handling of escaped unicode
+%%   codepoint sequences. if the ascii option is present, the sequence is converted
+%%   to a codepoint and inserted into the string if it represents an ascii value. if 
+%%   the codepoint option is present the sequence is converted and inserted as long
+%%   as it represents a valid unicode codepoint. this means non-characters 
+%%   representable in 16 bits are not converted (the utf16 surrogates and the two
+%%   special non-characters). any other option and no conversion is done.
+
+escaped_unicode(<<D/?encoding, Rest/binary>>, 
+        Stack, 
+        Callbacks, 
+        ?escaped_unicode_to_ascii(Opts), 
+        String, 
+        [C, B, A]) 
+            when ?is_hex(D) ->
+    case erlang:list_to_integer([A, B, C, D], 16) of
+        X when X < 128 ->
+            string(Rest, Stack, Callbacks, Opts, [X] ++ String)
+        ; _ ->
+            string(Rest, Stack, Callbacks, Opts, [D, C, B, A, $u, ?rsolidus] ++ String)
+    end;
+escaped_unicode(<<D/?encoding, Rest/binary>>, 
+        Stack, 
+        Callbacks, 
+        ?escaped_unicode_to_codepoint(Opts), 
+        String, 
+        [C, B, A]) 
+            when ?is_hex(D) ->
+    case erlang:list_to_integer([A, B, C, D], 16) of
+        X when X < 16#d800; X > 16#dfff, X < 16#fffe ->
+            string(Rest, Stack, Callbacks, Opts, [X] ++ String)
+        ; _ ->
+            string(Rest, Stack, Callbacks, Opts, [D, C, B, A, $u, ?rsolidus] ++ String)
+    end;
+escaped_unicode(<<D/?encoding, Rest/binary>>, Stack, Callbacks, Opts, String, [C, B, A]) when ?is_hex(D) ->
+    string(Rest, Stack, Callbacks, Opts, [D, C, B, A, $u, ?rsolidus] ++ String);
+escaped_unicode(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, String, Acc) when ?is_hex(S) ->
+    escaped_unicode(Rest, Stack, Callbacks, Opts, String, [S] ++ Acc);
+escaped_unicode(Bin, Stack, Callbacks, Opts, String, Acc) ->
+    {incomplete, fun(Stream) -> escaped_unicode(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, String, Acc) end}.
+
+
+%% like strings, numbers are collected in an intermediate accumulator before
+%%   being emitted to the callback handler. no processing of numbers is done in
+%%   process, it's left for the user, though there are convenience functions to
+%%   convert them into erlang floats/integers in jsx_utils.erl.
+
+%% TODO: actually write that jsx_utils.erl module mentioned above...
+
+negative(<<$0/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    zero(Rest, Stack, Callbacks, Opts, "0" ++ Acc);
+negative(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_nonzero(S) ->
+    integer(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
+negative(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> negative(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+zero(<<?end_object/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_object, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+zero(<<?end_array/?encoding, Rest/binary>>, [array|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_array, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+zero(<<?comma/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    key(Rest, [key|Stack], fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+zero(<<?comma/?encoding, Rest/binary>>, [array|_] = Stack, Callbacks, Opts, Acc) ->
+    value(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+zero(<<?decimalpoint/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    fraction(Rest, Stack, Callbacks, Opts, [?decimalpoint] ++ Acc);
+zero(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_whitespace(S) ->
+    maybe_done(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+zero(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts), Acc) ->
+    maybe_comment(Rest, fun(Resume) -> zero(Resume, Stack, Callbacks, Opts, Acc) end);
+zero(<<>>, [], Callbacks, Opts, Acc) ->
+    {fold(end_of_stream, fold({number, lists:reverse(Acc)}, Callbacks)), 
+        fun(Stream) -> zero(Stream, [], Callbacks, Opts, Acc) end};
+zero(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> zero(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+integer(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_nonzero(S) ->
+    integer(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
+integer(<<?end_object/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_object, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+integer(<<?end_array/?encoding, Rest/binary>>, [array|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_array, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+integer(<<?comma/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    key(Rest, [key|Stack], fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+integer(<<?comma/?encoding, Rest/binary>>, [array|_] = Stack, Callbacks, Opts, Acc) ->
+    value(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+integer(<<?decimalpoint/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    fraction(Rest, Stack, Callbacks, Opts, [?decimalpoint] ++ Acc);
+integer(<<?zero/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    integer(Rest, Stack, Callbacks, Opts, [?zero] ++ Acc);
+integer(<<$e/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    e(Rest, Stack, Callbacks, Opts, "e" ++ Acc);
+integer(<<$E/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    e(Rest, Stack, Callbacks, Opts, "e" ++ Acc);
+integer(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_whitespace(S) ->
+    maybe_done(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+integer(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts), Acc) ->
+    maybe_comment(Rest, fun(Resume) -> integer(Resume, Stack, Callbacks, Opts, Acc) end);
+integer(<<>>, [], Callbacks, Opts, Acc) ->
+    {fold(end_of_stream, fold({number, lists:reverse(Acc)}, Callbacks)), 
+        fun(Stream) -> integer(Stream, [], Callbacks, Opts, Acc) end};
+integer(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> integer(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+fraction(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_nonzero(S) ->
+    fraction(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
+fraction(<<?end_object/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_object, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+fraction(<<?end_array/?encoding, Rest/binary>>, [array|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_array, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+fraction(<<?comma/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    key(Rest, [key|Stack], fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+fraction(<<?comma/?encoding, Rest/binary>>, [array|_] = Stack, Callbacks, Opts, Acc) ->
+    value(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+fraction(<<?zero/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    fraction(Rest, Stack, Callbacks, Opts, [?zero] ++ Acc);
+fraction(<<$e/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    e(Rest, Stack, Callbacks, Opts, "e" ++ Acc);
+fraction(<<$E/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    e(Rest, Stack, Callbacks, Opts, "e" ++ Acc);
+fraction(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_whitespace(S) ->
+    maybe_done(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+fraction(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts), Acc) ->
+    maybe_comment(Rest, fun(Resume) -> fraction(Resume, Stack, Callbacks, Opts, Acc) end);
+fraction(<<>>, [], Callbacks, Opts, Acc) ->
+    {fold(end_of_stream, fold({number, lists:reverse(Acc)}, Callbacks)), 
+        fun(Stream) -> fraction(Stream, [], Callbacks, Opts, Acc) end};
+fraction(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> fraction(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+e(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when S =:= ?zero; ?is_nonzero(S) ->
+    exp(Rest, Stack, Callbacks, Opts, [S] ++ Acc);   
+e(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when S =:= ?positive; S =:= ?negative ->
+    ex(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
+e(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> e(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+ex(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when S =:= ?zero; ?is_nonzero(S) ->
+    exp(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
+ex(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> ex(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+exp(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_nonzero(S) ->
+    exp(Rest, Stack, Callbacks, Opts, [S] ++ Acc);
+exp(<<?end_object/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_object, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+exp(<<?end_array/?encoding, Rest/binary>>, [array|Stack], Callbacks, Opts, Acc) ->
+    maybe_done(Rest, Stack, fold(end_array, fold({number, lists:reverse(Acc)}, Callbacks)), Opts);
+exp(<<?comma/?encoding, Rest/binary>>, [object|Stack], Callbacks, Opts, Acc) ->
+    key(Rest, [key|Stack], fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+exp(<<?comma/?encoding, Rest/binary>>, [array|_] = Stack, Callbacks, Opts, Acc) ->
+    value(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+exp(<<?zero/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) ->
+    exp(Rest, Stack, Callbacks, Opts, [?zero] ++ Acc);
+exp(<<?solidus/?encoding, Rest/binary>>, Stack, Callbacks, ?comments_enabled(Opts), Acc) ->
+    maybe_comment(Rest, fun(Resume) -> exp(Resume, Stack, Callbacks, Opts, Acc) end);
+exp(<<S/?encoding, Rest/binary>>, Stack, Callbacks, Opts, Acc) when ?is_whitespace(S) ->
+    maybe_done(Rest, Stack, fold({number, lists:reverse(Acc)}, Callbacks), Opts);
+exp(<<>>, [], Callbacks, Opts, Acc) ->
+    {fold(end_of_stream, fold({number, lists:reverse(Acc)}, Callbacks)), 
+        fun(Stream) -> exp(Stream, [], Callbacks, Opts, Acc) end};
+exp(Bin, Stack, Callbacks, Opts, Acc) ->
+    {incomplete, fun(Stream) -> exp(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts, Acc) end}.
+
+
+tr(<<$r/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    tru(Rest, Stack, Callbacks, Opts);
+tr(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> tr(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+tru(<<$u/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    true(Rest, Stack, Callbacks, Opts);
+tru(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> tru(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+true(<<$e/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    maybe_done(Rest, Stack, fold({literal, true}, Callbacks), Opts);
+true(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> true(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+fa(<<$a/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    fal(Rest, Stack, Callbacks, Opts);
+fa(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> fa(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+fal(<<$l/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    fals(Rest, Stack, Callbacks, Opts);
+fal(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> fal(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+fals(<<$s/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    false(Rest, Stack, Callbacks, Opts);
+fals(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> fals(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+false(<<$e/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    maybe_done(Rest, Stack, fold({literal, false}, Callbacks), Opts);
+false(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> false(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+nu(<<$u/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    nul(Rest, Stack, Callbacks, Opts);
+nu(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> nu(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+nul(<<$l/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    null(Rest, Stack, Callbacks, Opts);
+nul(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> nul(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.
+
+
+null(<<$l/?encoding, Rest/binary>>, Stack, Callbacks, Opts) ->
+    maybe_done(Rest, Stack, fold({literal, null}, Callbacks), Opts);
+null(Bin, Stack, Callbacks, Opts) ->
+    {incomplete, fun(Stream) -> null(<<Bin/binary, Stream/binary>>, Stack, Callbacks, Opts) end}.    
+
+
+%% comments are c style, /* blah blah */ and are STRONGLY discouraged. any unicode
+%%   character is valid in a comment, except, obviously the */ sequence which ends
+%%   the comment. they're implemented as a closure called when the comment ends that
+%%   returns execution to the point where the comment began. comments are not 
+%%   recorded in any way, simply parsed.    
+
+maybe_comment(<<?star/?encoding, Rest/binary>>, Resume) ->
+    comment(Rest, Resume);
+maybe_comment(Bin, Resume) ->
+    {incomplete, fun(Stream) -> maybe_comment(<<Bin/binary, Stream/binary>>, Resume) end}.
+
+
+comment(<<?star/?encoding, Rest/binary>>, Resume) ->
+    maybe_comment_done(Rest, Resume);
+comment(<<_/?encoding, Rest/binary>>, Resume) ->
+    comment(Rest, Resume);
+comment(Bin, Resume) ->
+    {incomplete, fun(Stream) -> comment(<<Bin/binary, Stream/binary>>, Resume) end}.
+
+
+maybe_comment_done(<<?solidus/?encoding, Rest/binary>>, Resume) ->
+    Resume(Rest);
+maybe_comment_done(Bin, Resume) ->
+    {incomplete, fun(Stream) -> maybe_comment_done(<<Bin/binary, Stream/binary>>, Resume) end}.
\ No newline at end of file