delistify README
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alisdair sullivan
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572
README.markdown
572
README.markdown
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@ -25,74 +25,74 @@ jsx may be built using either [sinan][sinan] or [rebar][rebar]
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## quickstart ##
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* to build the library and run tests
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#### to build the library and run tests ####
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```bash
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tanga:jsx alisdair$ sinan build
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tanga:jsx alisdair$ sinan -r tests eunit
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```
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or
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```bash
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tanga:jsx alisdair$ rebar compile
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tanga:jsx alisdair$ rebar eunit
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```
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```bash
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tanga:jsx alisdair$ sinan build
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tanga:jsx alisdair$ sinan -r tests eunit
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```
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or
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```bash
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tanga:jsx alisdair$ rebar compile
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tanga:jsx alisdair$ rebar eunit
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```
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* to convert a utf8 binary containing a json string into an erlang term
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#### to convert a utf8 binary containing a json string into an erlang term ####
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```erlang
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1> jsx:decode(<<"{\"library\": \"jsx\", \"awesome\": true}">>).
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[{<<"library">>,<<"jsx">>},{<<"awesome">>,true}]
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2> jsx:decode(<<"[\"a\",\"list\",\"of\",\"words\"]">>).
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[<<"a">>, <<"list">>, <<"of">>, <<"words">>]
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```
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```erlang
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1> jsx:decode(<<"{\"library\": \"jsx\", \"awesome\": true}">>).
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[{<<"library">>,<<"jsx">>},{<<"awesome">>,true}]
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2> jsx:decode(<<"[\"a\",\"list\",\"of\",\"words\"]">>).
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[<<"a">>, <<"list">>, <<"of">>, <<"words">>]
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```
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* to convert an erlang term into a utf8 binary containing a json string
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#### to convert an erlang term into a utf8 binary containing a json string ####
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```erlang
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1> jsx:encode([{<<"library">>,<<"jsx">>},{<<"awesome">>,true}]).
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<<"{\"library\": \"jsx\", \"awesome\": true}">>
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2> jsx:encode([<<"a">>, <<"list">>, <<"of">>, <<"words">>]).
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<<"[\"a\",\"list\",\"of\",\"words\"]">>
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```
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```erlang
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1> jsx:encode([{<<"library">>,<<"jsx">>},{<<"awesome">>,true}]).
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<<"{\"library\": \"jsx\", \"awesome\": true}">>
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2> jsx:encode([<<"a">>, <<"list">>, <<"of">>, <<"words">>]).
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<<"[\"a\",\"list\",\"of\",\"words\"]">>
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```
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* to check if a binary or a term is valid json
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#### to check if a binary or a term is valid json ####
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```erlang
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1> jsx:is_json(<<"[\"this is json\"]">>).
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true
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2> jsx:is_json("[\"this is not\"]").
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false
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3> jsx:is_term([<<"this is a term">>]).
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true
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4> jsx:is_term(["this is not"]).
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false
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```
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```erlang
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1> jsx:is_json(<<"[\"this is json\"]">>).
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true
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2> jsx:is_json("[\"this is not\"]").
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false
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3> jsx:is_term([<<"this is a term">>]).
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true
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4> jsx:is_term(["this is not"]).
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false
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```
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* to minify some json
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#### to minify some json ####
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```erlang
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1> jsx:minify(<<"{
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\"a list\": [
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1,
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2,
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3
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]
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}">>).
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<<"{\"a list\":[1,2,3]}">>
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```
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```erlang
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1> jsx:minify(<<"{
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\"a list\": [
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1,
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2,
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3
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]
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}">>).
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<<"{\"a list\":[1,2,3]}">>
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```
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* to prettify some json
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#### to prettify some json ####
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```erlang
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1> jsx:prettify(<<"{\"a list\":[1,2,3]}">>).
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<<"{
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\"a list\": [
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1,
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2,
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3
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]
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}">>
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```
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```erlang
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1> jsx:prettify(<<"{\"a list\":[1,2,3]}">>).
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<<"{
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\"a list\": [
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1,
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2,
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3
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]
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}">>
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```
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## description ##
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@ -108,7 +108,7 @@ the [spec][rfc4627] thinks json values must be wrapped in a json array or object
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here is a table of how various json values map to erlang:
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#### json <-> erlang mapping ####
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### json <-> erlang mapping ###
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**json** | **erlang**
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--------------------------------|--------------------------------
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@ -149,7 +149,7 @@ here is a table of how various json values map to erlang:
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json objects are represented by erlang proplists. the empty object has the special representation `[{}]` to differentiate it from the empty list. ambiguities like `[true, false]` prevent the use of the shorthand form of property lists using atoms as properties so all properties must be tuples. all keys must be encoded as in `string` or as atoms (which will be escaped and converted to binaries for presentation to handlers). values should be valid json values
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#### incomplete input ####
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### incomplete input ###
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jsx handles incomplete json texts. if a partial json text is parsed, rather than returning a term from your callback handler, jsx returns `{incomplete, F}` where `F` is a function with an identical API to the anonymous fun returned from `decoder/3`, `encoder/3` or `parser/3`. it retains the internal state of the parser at the point where input was exhausted. this allows you to parse as you stream json over a socket or file descriptor, or to parse large json texts without needing to keep them entirely in memory
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@ -158,104 +158,100 @@ however, it is important to recognize that jsx is greedy by default. jsx will co
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## data types ##
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* `json_term()`
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#### `json_term()` ####
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```erlang
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json_term() = [json_term()]
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| [{binary() | atom(), json_term()}]
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| true
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| false
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| null
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| integer()
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| float()
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| binary()
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```
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```erlang
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json_term() = [json_term()]
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| [{binary() | atom(), json_term()}]
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| true
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| false
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| null
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| integer()
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| float()
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| binary()
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```
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the erlang representation of json. binaries should be `utf8` encoded, or close at least
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the erlang representation of json. binaries should be `utf8` encoded, or close at least
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* `json_text()`
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#### `json_text()` ####
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```erlang
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json_text() = binary()
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```
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```erlang
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json_text() = binary()
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```
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a utf8 encoded binary containing a json string
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a utf8 encoded binary containing a json string
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* `tokens()` & `token()`
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#### `token()` ####
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```erlang
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tokens() = token() | [token()]
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token() = start_object
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| end_object
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| start_array
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| end_array
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| {key, binary()}
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| {string, binary()}
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| binary()
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| {number, integer() | float()}
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| {integer, integer()}
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| {float, float()}
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| integer()
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| float()
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| {literal, true}
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| {literal, false}
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| {literal, null}
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| true
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| false
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| null
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| end_json
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```
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```erlang
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token() = start_object
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| end_object
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| start_array
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| end_array
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| {key, binary()}
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| {string, binary()}
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| binary()
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| {number, integer() | float()}
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| {integer, integer()}
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| {float, float()}
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| integer()
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| float()
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| {literal, true}
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| {literal, false}
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| {literal, null}
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| true
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| false
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| null
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| end_json
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```
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the internal representation used during syntactic analysis
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the internal representation used during syntactic analysis
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* `events()` & `event()`
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#### `event()` ####
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```erlang
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event() = start_object
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| end_object
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| start_array
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| end_array
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| {key, binary()}
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| {string, binary()}
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| {integer, integer()}
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| {float, float()}
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| {literal, true}
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| {literal, false}
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| {literal, null}
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| end_json
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```
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```erlang
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event() = start_object
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| end_object
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| start_array
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| end_array
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| {key, binary()}
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| {string, binary()}
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| {integer, integer()}
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| {float, float()}
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| {literal, true}
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| {literal, false}
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| {literal, null}
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| end_json
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```
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the internal representation used during semantic analysis
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the internal representation used during semantic analysis
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* `options()` & `option()`
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#### `option()` ####
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```erlang
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options() = [option()]
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```erlang
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option() = replaced_bad_utf8
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| escaped_forward_slashes
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| single_quoted_strings
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| unescaped_jsonp
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| comments
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| escaped_strings
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| dirty_strings
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| ignored_bad_escapes
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| relax
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| explicit_end
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```
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option() = replaced_bad_utf8
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| escaped_forward_slashes
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| single_quoted_strings
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| unescaped_jsonp
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| comments
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| escaped_strings
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| dirty_strings
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| ignored_bad_escapes
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| relax
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| explicit_end
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```
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jsx functions all take a common set of options. not all flags have meaning in all contexts, but they are always valid options. functions may have additional options beyond these. see [individual function documentation](#exports) for details
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jsx functions all take a common set of options. not all flags have meaning in all contexts, but they are always valid options. functions may have additional options beyond these. see [individual function documentation](#exports) for details
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- `replaced_bad_utf8`
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- `replaced_bad_utf8`
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json text input and json strings SHOULD be utf8 encoded binaries, appropriately escaped as per the json spec. attempts are made to replace invalid codepoints with `u+FFFD` as per the unicode spec when this option is present. this applies both to malformed unicode and disallowed codepoints
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- `escaped_forward_slashes`
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- `escaped_forward_slashes`
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json strings are escaped according to the json spec. this means forward slashes (solidus) are optionally escaped. this option is only relevant for encoding; you may want to use this if you are embedding json directly into a html or xml document
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- `single_quoted_strings`
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- `single_quoted_strings`
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some parsers allow double quotes (`u+0022`) to be replaced by single quotes (`u+0027`) to delimit keys and strings. this option allows json containing single quotes as structural characters to be parsed without errors. note that the parser expects strings to be terminated by the same quote type that opened it and that single quotes must, obviously, be escaped within strings delimited by single quotes
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@ -263,31 +259,31 @@ however, it is important to recognize that jsx is greedy by default. jsx will co
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the parser will never emit json with keys or strings delimited by single quotes
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- `unescaped_jsonp`
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- `unescaped_jsonp`
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javascript interpreters treat the codepoints `u+2028` and `u+2029` as significant whitespace. json strings that contain either of these codepoints will be parsed incorrectly by some javascript interpreters. by default, these codepoints are escaped (to `\u2028` and `\u2029`, respectively) to retain compatibility. this option simply removes that escaping
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- `comments`
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- `comments`
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json has no official comments but some parsers allow c style comments. anywhere whitespace is allowed this flag allows comments (both `// ...` and `/* ... */` style)
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- `escaped_strings`
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- `escaped_strings`
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by default, both the encoder and decoder return strings as utf8 binaries appropriate for use in erlang. escape sequences that were present in decoded terms are converted into the appropriate codepoint while encoded terms are unaltered. this flag escapes strings as if for output in json, removing control codes and problematic codepoints and replacing them with the appropriate escapes
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- `dirty_strings`
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- `dirty_strings`
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json escaping is lossy; it mutates the json string and repeated application can result in unwanted behaviour. if your strings are already escaped (or you'd like to force invalid strings into "json") use this flag to bypass escaping
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- `ignored_bad_escapes`
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- `ignored_bad_escapes`
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during decoding, ignore unrecognized escape sequences and leave them as is in the stream. note that combining this option with `escaped_strings` will result in the escape character itself being escaped
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- `explicit_end`
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- `explicit_end`
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this option treats all exhausted inputs as incomplete. the parser will not attempt to return a final state until the function is called with the value `end_stream`
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- `relax`
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- `relax`
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relax is a synonym for `[replaced_bad_utf8, single_quoted_strings, comments, ignored_bad_escapes]` for when you don't care how janky and awful your json input is, you just want the parser to do the best it can
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@ -295,245 +291,245 @@ however, it is important to recognize that jsx is greedy by default. jsx will co
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## exports ##
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* `encoder/3`, `decoder/3` & `parser/3`
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#### `encoder/3`, `decoder/3` & `parser/3` ####
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```erlang
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decoder(Module, Args, Opts) -> Fun((JSONText) -> any())
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encoder(Module, Args, Opts) -> Fun((JSONTerm) -> any())
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parser(Module, Args, Opts) -> Fun((Tokens) -> any())
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```erlang
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decoder(Module, Args, Opts) -> Fun((JSONText) -> any())
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encoder(Module, Args, Opts) -> Fun((JSONTerm) -> any())
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parser(Module, Args, Opts) -> Fun((Tokens) -> any())
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Module = atom()
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Args = any()
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Opts = options()
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JSONText = json_text()
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JSONTerm = json_term()
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Tokens = tokens()
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```
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Module = atom()
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Args = any()
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Opts = [option()]
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JSONText = json_text()
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JSONTerm = json_term()
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Tokens = token() | [token()]
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```
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jsx is a json compiler with distinct tokenizing, syntactic analysis and semantic analysis stages (actually, semantic analysis takes place during syntactic analysis, for efficiency). included are two tokenizers; one that handles json texts (`decoder/3`) and one that handles erlang terms (`encoder/3`). there is also an entry point to the syntactic analysis stage for use with user-defined tokenizers (`parser/3`)
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jsx is a json compiler with interleaved tokenizing, syntactic analysis and semantic analysis stages. included are two tokenizers; one that handles json texts (`decoder/3`) and one that handles erlang terms (`encoder/3`). there is also an entry point to the syntactic analysis stage for use with user-defined tokenizers (`parser/3`)
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all three functions return an anonymous function that takes the appropriate type of input and returns the result of performing semantic analysis, the tuple `{incomplete, F}` where `F` is a new anonymous function (see [incomplete input](#incomplete_input)) or a `badarg` error exception if syntactic analysis fails
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all three functions return an anonymous function that takes the appropriate type of input and returns the result of performing semantic analysis, the tuple `{incomplete, F}` where `F` is a new anonymous function (see [incomplete input](#incomplete_input)) or a `badarg` error exception if syntactic analysis fails
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`Module` is the name of the callback module
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`Module` is the name of the callback module
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`Args` is any term that will be passed to `Module:init/1` prior to syntactic analysis to produce an initial state
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`Args` is any term that will be passed to `Module:init/1` prior to syntactic analysis to produce an initial state
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`Opts` are detailed in [data types](#data_types)
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`Opts` are detailed in [data types](#data_types)
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see [callback exports](#callback_exports) for details on the callback module
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check out [callback module documentation](#callback_exports) for details of the callback module interface
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* `decode/1,2`
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#### `decode/1,2` ####
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```erlang
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decode(JSON) -> Term
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decode(JSON, Opts) -> Term
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```erlang
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decode(JSON) -> Term
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decode(JSON, Opts) -> Term
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JSON = json_text()
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Term = json_term()
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Opts = [option() | labels | {labels, Label} | {post_decode, F}]
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Label = binary | atom | existing_atom
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F = fun((any()) -> any())
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```
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JSON = json_text()
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Term = json_term()
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Opts = [option() | labels | {labels, Label} | {post_decode, F}]
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Label = binary | atom | existing_atom
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F = fun((any()) -> any())
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```
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`decode` parses a json text (a `utf8` encoded binary) and produces an erlang term (see [json <-> erlang mapping](#json---erlang-mapping))
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`decode` parses a json text (a `utf8` encoded binary) and produces an erlang term
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the option `labels` controls how keys are converted from json to erlang terms. `binary` does no conversion beyond normal escaping. `atom` converts keys to erlang atoms and results in a badarg error if the keys fall outside the range of erlang atoms. `existing_atom` is identical to `atom` except it will not add new atoms to the atom table
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the option `labels` controls how keys are converted from json to erlang terms. `binary` does no conversion beyond normal escaping. `atom` converts keys to erlang atoms and results in a badarg error if the keys fall outside the range of erlang atoms. `existing_atom` is identical to `atom` except it will not add new atoms to the atom table
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`{post_decode, F}` is a user defined function of arity 1 that is called on each output value (objects, arrays, strings, numbers and literals). it may return any value to be substituted in the returned term. for example:
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`{post_decode, F}` is a user defined function of arity 1 that is called on each output value (objects, arrays, strings, numbers and literals). it may return any value to be substituted in the returned term. for example:
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```erlang
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1> F = fun(V) when is_list(V) -> V; (V) -> false end.
|
||||
2> jsx:decode(<<"{\"a list\": [true, \"a string\", 1]}">>, [{post_decode, F}]).
|
||||
[{<<"a list">>, [false, false, false]}]
|
||||
```
|
||||
```erlang
|
||||
1> F = fun(V) when is_list(V) -> V; (V) -> false end.
|
||||
2> jsx:decode(<<"{\"a list\": [true, \"a string\", 1]}">>, [{post_decode, F}]).
|
||||
[{<<"a list">>, [false, false, false]}]
|
||||
```
|
||||
|
||||
declaring more than one post-decoder will result in a `badarg` error exception
|
||||
declaring more than one post-decoder will result in a `badarg` error exception
|
||||
|
||||
raises a `badarg` error exception if input is not valid json
|
||||
raises a `badarg` error exception if input is not valid json
|
||||
|
||||
|
||||
* `encode/1,2`
|
||||
#### `encode/1,2` ####
|
||||
|
||||
```erlang
|
||||
encode(Term) -> JSON
|
||||
encode(Term, Opts) -> JSON
|
||||
```erlang
|
||||
encode(Term) -> JSON
|
||||
encode(Term, Opts) -> JSON
|
||||
|
||||
Term = json_term()
|
||||
JSON = json_text()
|
||||
Opts = [option() | {pre_encode, F} | space | {space, N} | indent | {indent, N}]
|
||||
F = fun((any()) -> any())
|
||||
N = pos_integer()
|
||||
```
|
||||
Term = json_term()
|
||||
JSON = json_text()
|
||||
Opts = [option() | {pre_encode, F} | space | {space, N} | indent | {indent, N}]
|
||||
F = fun((any()) -> any())
|
||||
N = pos_integer()
|
||||
```
|
||||
|
||||
`encode` parses a json text (a `utf8` encoded binary) and produces an erlang term (see [json <-> erlang mapping](#json---erlang-mapping))
|
||||
`encode` parses a json text (a `utf8` encoded binary) and produces an erlang term
|
||||
|
||||
the option `{space, N}` inserts `N` spaces after every comma and colon in your json output. `space` is an alias for `{space, 1}`. the default is `{space, 0}`
|
||||
the option `{space, N}` inserts `N` spaces after every comma and colon in your json output. `space` is an alias for `{space, 1}`. the default is `{space, 0}`
|
||||
|
||||
the option `{indent, N}` inserts a newline and `N` spaces for each level of indentation in your json output. note that this overrides spaces inserted after a comma. `indent` is an alias for `{indent, 1}`. the default is `{indent, 0}`
|
||||
the option `{indent, N}` inserts a newline and `N` spaces for each level of indentation in your json output. note that this overrides spaces inserted after a comma. `indent` is an alias for `{indent, 1}`. the default is `{indent, 0}`
|
||||
|
||||
`{pre_encode, F}` is a user defined function of arity 1 that is called on each input value. it may return any valid json value to be substituted in the returned json. for example:
|
||||
`{pre_encode, F}` is a user defined function of arity 1 that is called on each input value. it may return any valid json value to be substituted in the returned json. for example:
|
||||
|
||||
```erlang
|
||||
1> F = fun(V) when is_list(V) -> V; (V) -> false end.
|
||||
2> jsx:encode([{<<"a list">>, [true, <<"a string">>, 1]}], [{pre_encode, F}]).
|
||||
<<"{\"a list\": [false, false, false]}">>
|
||||
```
|
||||
```erlang
|
||||
1> F = fun(V) when is_list(V) -> V; (V) -> false end.
|
||||
2> jsx:encode([{<<"a list">>, [true, <<"a string">>, 1]}], [{pre_encode, F}]).
|
||||
<<"{\"a list\": [false, false, false]}">>
|
||||
```
|
||||
|
||||
declaring more than one pre-encoder will result in a `badarg` error exception
|
||||
declaring more than one pre-encoder will result in a `badarg` error exception
|
||||
|
||||
raises a `badarg` error exception if input is not a valid erlang representation of json
|
||||
raises a `badarg` error exception if input is not a valid [erlang representation of json](#json---erlang-mapping)
|
||||
|
||||
|
||||
* `format/1,2`
|
||||
#### `format/1,2` ####
|
||||
|
||||
```erlang
|
||||
format(JSON) -> JSON
|
||||
format(JSON, Opts) -> JSON
|
||||
```erlang
|
||||
format(JSON) -> JSON
|
||||
format(JSON, Opts) -> JSON
|
||||
|
||||
JSON = json_text()
|
||||
Opts = [option() | space | {space, N} | indent | {indent, N}]
|
||||
N = pos_integer()
|
||||
```
|
||||
JSON = json_text()
|
||||
Opts = [option() | space | {space, N} | indent | {indent, N}]
|
||||
N = pos_integer()
|
||||
```
|
||||
|
||||
`format` parses a json text (a `utf8` encoded binary) and produces a new json text according to the format rules specified by `Opts`
|
||||
`format` parses a json text (a `utf8` encoded binary) and produces a new json text according to the format rules specified by `Opts`
|
||||
|
||||
the option `{space, N}` inserts `N` spaces after every comma and colon in your json output. `space` is an alias for `{space, 1}`. the default is `{space, 0}`
|
||||
|
||||
the option `{indent, N}` inserts a newline and `N` spaces for each level of indentation in your json output. note that this overrides spaces inserted after a comma. `indent` is an alias for `{indent, 1}`. the default is `{indent, 0}`
|
||||
the option `{space, N}` inserts `N` spaces after every comma and colon in your json output. `space` is an alias for `{space, 1}`. the default is `{space, 0}`
|
||||
|
||||
raises a `badarg` error exception if input is not valid json
|
||||
the option `{indent, N}` inserts a newline and `N` spaces for each level of indentation in your json output. note that this overrides spaces inserted after a comma. `indent` is an alias for `{indent, 1}`. the default is `{indent, 0}`
|
||||
|
||||
raises a `badarg` error exception if input is not valid json
|
||||
|
||||
|
||||
* `minify/1`
|
||||
#### `minify/1` ####
|
||||
|
||||
```erlang
|
||||
minify(JSON) -> JSON
|
||||
```erlang
|
||||
minify(JSON) -> JSON
|
||||
|
||||
JSON = json_text()
|
||||
```
|
||||
JSON = json_text()
|
||||
```
|
||||
|
||||
`minify` parses a json text (a `utf8` encoded binary) and produces a new json text stripped of whitespace
|
||||
`minify` parses a json text (a `utf8` encoded binary) and produces a new json text stripped of whitespace
|
||||
|
||||
raises a `badarg` error exception if input is not valid json
|
||||
raises a `badarg` error exception if input is not valid json
|
||||
|
||||
|
||||
* `prettify/1`
|
||||
#### `prettify/1` ####
|
||||
|
||||
```erlang
|
||||
prettify(JSON) -> JSON
|
||||
```erlang
|
||||
prettify(JSON) -> JSON
|
||||
|
||||
JSON = json_text()
|
||||
```
|
||||
JSON = json_text()
|
||||
```
|
||||
|
||||
`prettify` parses a json text (a `utf8` encoded binary) and produces a new json text equivalent to `format(JSON, [{space, 1}, {indent, 2}])`
|
||||
`prettify` parses a json text (a `utf8` encoded binary) and produces a new json text equivalent to `format(JSON, [{space, 1}, {indent, 2}])`
|
||||
|
||||
raises a `badarg` error exception if input is not valid json
|
||||
raises a `badarg` error exception if input is not valid json
|
||||
|
||||
|
||||
* `is_json/1,2`
|
||||
#### `is_json/1,2` ####
|
||||
|
||||
```erlang
|
||||
is_json(MaybeJSON) -> true | false
|
||||
is_json(MaybeJSON, Opts) -> true | false
|
||||
```erlang
|
||||
is_json(MaybeJSON) -> true | false
|
||||
is_json(MaybeJSON, Opts) -> true | false
|
||||
|
||||
MaybeJSON = any()
|
||||
Opts = options()
|
||||
```
|
||||
MaybeJSON = any()
|
||||
Opts = options()
|
||||
```
|
||||
|
||||
returns true if input is a valid json text, false if not
|
||||
returns true if input is a valid json text, false if not
|
||||
|
||||
what exactly constitutes valid json may be altered per the options, detailed in [data types](#data_types)
|
||||
what exactly constitutes valid json may be altered per the options, detailed in [data types](#data_types)
|
||||
|
||||
|
||||
* `is_term/1,2`
|
||||
#### `is_term/1,2` ####
|
||||
|
||||
```erlang
|
||||
is_term(MaybeJSON) -> true | false
|
||||
is_term(MaybeJSON, Opts) -> true | false
|
||||
```erlang
|
||||
is_term(MaybeJSON) -> true | false
|
||||
is_term(MaybeJSON, Opts) -> true | false
|
||||
|
||||
MaybeJSON = any()
|
||||
Opts = options()
|
||||
```
|
||||
MaybeJSON = any()
|
||||
Opts = options()
|
||||
```
|
||||
|
||||
returns true if input is a valid erlang representation of json, false if not
|
||||
returns true if input is a valid erlang representation of json, false if not
|
||||
|
||||
what exactly constitutes valid json may be altered per the options, detailed in [data types](#data_types)
|
||||
what exactly constitutes valid json may be altered per the options, detailed in [data types](#data_types)
|
||||
|
||||
|
||||
## callback exports ##
|
||||
|
||||
the following functions should be exported from a jsx callback module
|
||||
|
||||
* `Module:init/1`
|
||||
#### `Module:init/1` ####
|
||||
|
||||
```erlang
|
||||
Module:init(Args) -> InitialState
|
||||
```erlang
|
||||
Module:init(Args) -> InitialState
|
||||
|
||||
Args = any()
|
||||
InitialState = any()
|
||||
```
|
||||
Args = any()
|
||||
InitialState = any()
|
||||
```
|
||||
|
||||
whenever any of `encoder/3`, `decoder/3` or `parser/3` are called, this function is called with the `Args` argument provided in the calling function to obtain `InitialState`
|
||||
whenever any of `encoder/3`, `decoder/3` or `parser/3` are called, this function is called with the `Args` argument provided in the calling function to obtain `InitialState`
|
||||
|
||||
* `Module:handle_event/2`
|
||||
#### `Module:handle_event/2` ####
|
||||
|
||||
```erlang
|
||||
Module:handle_event(Event, State) -> NewState
|
||||
```erlang
|
||||
Module:handle_event(Event, State) -> NewState
|
||||
|
||||
Event = events()
|
||||
State = any()
|
||||
NewState = any()
|
||||
```
|
||||
Event = [event()]
|
||||
State = any()
|
||||
NewState = any()
|
||||
```
|
||||
|
||||
semantic analysis is performed by repeatedly calling `handle_event/2` with a stream of events emitted by the tokenizer and the current state. the new state returned is used as the input to the next call to `handle_event/2`. the following events must be handled:
|
||||
semantic analysis is performed by repeatedly calling `handle_event/2` with a stream of events emitted by the tokenizer and the current state. the new state returned is used as the input to the next call to `handle_event/2`. the following events must be handled:
|
||||
|
||||
- `start_object`
|
||||
|
||||
the start of a json object
|
||||
- `start_object`
|
||||
|
||||
- `end_object`
|
||||
|
||||
the end of a json object
|
||||
the start of a json object
|
||||
|
||||
- `start_array`
|
||||
- `end_object`
|
||||
|
||||
the start of a json array
|
||||
the end of a json object
|
||||
|
||||
- `end_array`
|
||||
- `start_array`
|
||||
|
||||
the end of a json array
|
||||
the start of a json array
|
||||
|
||||
- `{key, binary()}`
|
||||
- `end_array`
|
||||
|
||||
a key in a json object. this is guaranteed to follow either `start_object` or a json value. it will usually be a `utf8` encoded binary. see the options under [data types](#data_types) for possible exceptions
|
||||
the end of a json array
|
||||
|
||||
- `{string, binary()}`
|
||||
- `{key, binary()}`
|
||||
|
||||
a json string. it will usually be a `utf8` encoded binary. see the options under [data types](#data_types) for possible exceptions
|
||||
a key in a json object. this is guaranteed to follow either `start_object` or a json value. it will usually be a `utf8` encoded binary. see the options under [data types](#data_types) for possible exceptions
|
||||
|
||||
- `{integer, integer()}`
|
||||
- `{string, binary()}`
|
||||
|
||||
an erlang integer (bignum)
|
||||
a json string. it will usually be a `utf8` encoded binary. see the options under [data types](#data_types) for possible exceptions
|
||||
|
||||
- `{float, float()}`
|
||||
- `{integer, integer()}`
|
||||
|
||||
an erlang float
|
||||
an erlang integer (bignum)
|
||||
|
||||
- `{literal, true}`
|
||||
- `{float, float()}`
|
||||
|
||||
the atom `true`
|
||||
an erlang float
|
||||
|
||||
- `{literal, false}`
|
||||
- `{literal, true}`
|
||||
|
||||
the atom `false`
|
||||
the atom `true`
|
||||
|
||||
- `{literal, null}`
|
||||
- `{literal, false}`
|
||||
|
||||
the atom `null`
|
||||
the atom `false`
|
||||
|
||||
- `end_json`
|
||||
- `{literal, null}`
|
||||
|
||||
this event is emitted when syntactic analysis is completed. you should do any cleanup and return the result of your semantic analysis
|
||||
the atom `null`
|
||||
|
||||
- `end_json`
|
||||
|
||||
this event is emitted when syntactic analysis is completed. you should do any cleanup and return the result of your semantic analysis
|
||||
|
||||
|
||||
## acknowledgements ##
|
||||
|
|
|
|||
Loading…
Add table
Add a link
Reference in a new issue