make erlware_commons work on pre-R15 releases

Signed-off-by: Jordan Wilberding <diginux@gmail.com>

src/ec_dictionary.erl

@@ -41,6 +41,8 @@
 -type key(T) :: T.
 -type value(T) :: T.
 
+-ifdef(have_callback_support).
+
 -callback new() -> any().
 -callback has_key(key(any()), any()) -> boolean().
 -callback get(key(any()), any()) -> any().
@@ -52,6 +54,27 @@
 -callback from_list([{key(any()), value(any())}]) -> any().
 -callback keys(any()) -> [key(any())].
 
+-else.
+
+%% In the case where R14 or lower is being used to compile the system
+%% we need to export a behaviour info
+-export([behaviour_info/1]).
+-spec behaviour_info(atom()) -> [{atom(), arity()}] | undefined.
+behaviour_info(callbacks) ->
+    [{new, 0},
+     {has_key, 2},
+     {get, 2},
+     {add, 3},
+     {remove, 2},
+     {has_value, 2},
+     {size, 1},
+     {to_list, 1},
+     {from_list, 1},
+     {keys, 1}];
+behaviour_info(_Other) ->
+    undefined.
+-endif.
+
 %%%===================================================================
 %%% API
 %%%===================================================================