diff options
| -rw-r--r-- | lib/stdlib/doc/src/erl_internal.xml | 10 | ||||
| -rw-r--r-- | lib/stdlib/src/erl_internal.erl | 67 |
2 files changed, 77 insertions, 0 deletions
diff --git a/lib/stdlib/doc/src/erl_internal.xml b/lib/stdlib/doc/src/erl_internal.xml index cf49df0972..17cd0fb240 100644 --- a/lib/stdlib/doc/src/erl_internal.xml +++ b/lib/stdlib/doc/src/erl_internal.xml @@ -44,6 +44,16 @@ <funcs> <func> + <name name="add_predefined_functions" arity="1"/> + <fsummary>Add code for pre-defined functions.</fsummary> + <desc> + <p>Adds to <c><anno>Forms</anno></c> the code for the standard + pre-defined functions (such as <c>module_info/0</c>) that are + to be included in every module.</p> + </desc> + </func> + + <func> <name name="arith_op" arity="2"/> <fsummary>Test for an arithmetic operator.</fsummary> <desc> diff --git a/lib/stdlib/src/erl_internal.erl b/lib/stdlib/src/erl_internal.erl index 46059f42a5..5d6aa0ebe8 100644 --- a/lib/stdlib/src/erl_internal.erl +++ b/lib/stdlib/src/erl_internal.erl @@ -54,6 +54,8 @@ -export([is_type/2]). +-export([add_predefined_functions/1]). + %%--------------------------------------------------------------------------- %% Erlang builtin functions allowed in guards. @@ -569,3 +571,68 @@ is_type(term, 0) -> true; is_type(timeout, 0) -> true; is_type(tuple, 0) -> true; is_type(_, _) -> false. + +%%% +%%% Add and export the pre-defined functions: +%%% +%%% module_info/0 +%%% module_info/1 +%%% behaviour_info/1 (optional) +%%% + +-spec add_predefined_functions(Forms) -> UpdatedForms when + Forms :: [erl_parse:abstract_form() | erl_parse:form_info()], + UpdatedForms :: [erl_parse:abstract_form() | erl_parse:form_info()]. + +add_predefined_functions(Forms) -> + Forms ++ predefined_functions(Forms). + +predefined_functions(Forms) -> + Attrs = [{Name,Val} || {attribute,_,Name,Val} <- Forms], + {module,Mod} = lists:keyfind(module, 1, Attrs), + Callbacks = [Callback || {callback,Callback} <- Attrs], + OptionalCallbacks = get_optional_callbacks(Attrs), + Mpf1 = module_predef_func_beh_info(Callbacks, OptionalCallbacks), + Mpf2 = module_predef_funcs_mod_info(Mod), + Mpf = [erl_parse:new_anno(F) || F <- Mpf1++Mpf2], + Exp = [{F,A} || {function,_,F,A,_} <- Mpf], + [{attribute,0,export,Exp}|Mpf]. + +get_optional_callbacks(Attrs) -> + L = [O || {optional_callbacks,O} <- Attrs, is_fa_list(O)], + lists:append(L). + +is_fa_list([{FuncName, Arity}|L]) + when is_atom(FuncName), is_integer(Arity), Arity >= 0 -> + is_fa_list(L); +is_fa_list([]) -> true; +is_fa_list(_) -> false. + +module_predef_func_beh_info([], _) -> + []; +module_predef_func_beh_info(Callbacks0, OptionalCallbacks) -> + Callbacks = [FA || {{_,_}=FA,_} <- Callbacks0], + List = make_list(Callbacks), + OptionalList = make_list(OptionalCallbacks), + [{function,0,behaviour_info,1, + [{clause,0,[{atom,0,callbacks}],[],[List]}, + {clause,0,[{atom,0,optional_callbacks}],[],[OptionalList]}]}]. + +make_list([]) -> {nil,0}; +make_list([{Name,Arity}|Rest]) -> + {cons,0, + {tuple,0, + [{atom,0,Name}, + {integer,0,Arity}]}, + make_list(Rest)}. + +module_predef_funcs_mod_info(Mod) -> + ModAtom = {atom,0,Mod}, + [{function,0,module_info,0, + [{clause,0,[],[], + [{call,0,{remote,0,{atom,0,erlang},{atom,0,get_module_info}}, + [ModAtom]}]}]}, + {function,0,module_info,1, + [{clause,0,[{var,0,'X'}],[], + [{call,0,{remote,0,{atom,0,erlang},{atom,0,get_module_info}}, + [ModAtom,{var,0,'X'}]}]}]}]. |