%% The MIT License
%%
%% Copyright (c) 2009 Tom Preston-Werner <tom@mojombo.com>
%%
%% 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.
%% See the README at http://github.com/mojombo/mustache.erl for additional
%% documentation and usage examples.
-module(mustache). %% v0.1.0
-author("Tom Preston-Werner").
-export([compile/1, compile/2, render/1, render/2, render/3, get/2, get/3, escape/1, start/1]).
-record(mstate, {mod = undefined,
section_re = undefined,
tag_re = undefined}).
-ifdef(TEST).
-include_lib("eunit/include/eunit.hrl").
-endif.
compile(Body) when is_list(Body) ->
State = #mstate{},
CompiledTemplate = pre_compile(Body, State),
% io:format("~p~n~n", [CompiledTemplate]),
% io:format(CompiledTemplate ++ "~n", []),
{ok, Tokens, _} = erl_scan:string(CompiledTemplate),
{ok, [Form]} = erl_parse:parse_exprs(Tokens),
Bindings = erl_eval:new_bindings(),
{value, Fun, _} = erl_eval:expr(Form, Bindings),
Fun;
compile(Mod) ->
TemplatePath = template_path(Mod),
compile(Mod, TemplatePath).
compile(Mod, File) ->
code:purge(Mod),
{module, _} = code:load_file(Mod),
{ok, TemplateBin} = file:read_file(File),
Template = re:replace(TemplateBin, "\"", "\\\\\"", [global, {return,list}]),
State = #mstate{mod = Mod},
CompiledTemplate = pre_compile(Template, State),
% io:format("~p~n~n", [CompiledTemplate]),
% io:format(CompiledTemplate ++ "~n", []),
{ok, Tokens, _} = erl_scan:string(CompiledTemplate),
{ok, [Form]} = erl_parse:parse_exprs(Tokens),
Bindings = erl_eval:new_bindings(),
{value, Fun, _} = erl_eval:expr(Form, Bindings),
Fun.
render(Mod) ->
TemplatePath = template_path(Mod),
render(Mod, TemplatePath).
render(Body, Ctx) when is_list(Body) ->
TFun = compile(Body),
render(undefined, TFun, Ctx);
render(Mod, File) when is_list(File) ->
render(Mod, File, dict:new());
render(Mod, CompiledTemplate) ->
render(Mod, CompiledTemplate, dict:new()).
render(Mod, File, Ctx) when is_list(File) ->
CompiledTemplate = compile(Mod, File),
render(Mod, CompiledTemplate, Ctx);
render(Mod, CompiledTemplate, Ctx) ->
Ctx2 = dict:store('__mod__', Mod, Ctx),
lists:flatten(CompiledTemplate(Ctx2)).
pre_compile(T, State) ->
SectionRE = "\{\{\#([^\}]*)}}\s*(.+?){{\/\\1\}\}\s*",
{ok, CompiledSectionRE} = re:compile(SectionRE, [dotall]),
TagRE = "\{\{(#|=|!|<|>|\{)?(.+?)\\1?\}\}+",
{ok, CompiledTagRE} = re:compile(TagRE, [dotall]),
State2 = State#mstate{section_re = CompiledSectionRE, tag_re = CompiledTagRE},
"fun(Ctx) -> " ++
"CFun = fun(A, B) -> A end, " ++
compiler(T, State2) ++ " end.".
compiler(T, State) ->
Res = re:run(T, State#mstate.section_re),
case Res of
{match, [{M0, M1}, {N0, N1}, {C0, C1}]} ->
Front = string:substr(T, 1, M0),
Back = string:substr(T, M0 + M1 + 1),
Name = string:substr(T, N0 + 1, N1),
Content = string:substr(T, C0 + 1, C1),
"[" ++ compile_tags(Front, State) ++
" | [" ++ compile_section(Name, Content, State) ++
" | [" ++ compiler(Back, State) ++ "]]]";
nomatch ->
compile_tags(T, State)
end.
compile_section(Name, Content, State) ->
Mod = State#mstate.mod,
Result = compiler(Content, State),
"fun() -> " ++
"case mustache:get(" ++ Name ++ ", Ctx, " ++ atom_to_list(Mod) ++ ") of " ++
"true -> " ++
Result ++ "; " ++
"false -> " ++
"[]; " ++
"List when is_list(List) -> " ++
"[fun(Ctx) -> " ++ Result ++ " end(dict:merge(CFun, SubCtx, Ctx)) || SubCtx <- List]; " ++
"Else -> " ++
"throw({template, io_lib:format(\"Bad context for ~p: ~p\", [" ++ Name ++ ", Else])}) " ++
"end " ++
"end()".
compile_tags(T, State) ->
Res = re:run(T, State#mstate.tag_re),
case Res of
{match, [{M0, M1}, K, {C0, C1}]} ->
Front = string:substr(T, 1, M0),
Back = string:substr(T, M0 + M1 + 1),
Content = string:substr(T, C0 + 1, C1),
Kind = tag_kind(T, K),
Result = compile_tag(Kind, Content, State),
"[\"" ++ Front ++
"\" | [" ++ Result ++
" | " ++ compile_tags(Back, State) ++ "]]";
nomatch ->
"[\"" ++ T ++ "\"]"
end.
tag_kind(_T, {-1, 0}) ->
none;
tag_kind(T, {K0, K1}) ->
string:substr(T, K0 + 1, K1).
compile_tag(none, Content, State) ->
Mod = State#mstate.mod,
"mustache:escape(mustache:get(" ++ Content ++ ", Ctx, " ++ atom_to_list(Mod) ++ "))";
compile_tag("{", Content, State) ->
Mod = State#mstate.mod,
"mustache:get(" ++ Content ++ ", Ctx, " ++ atom_to_list(Mod) ++ ")";
compile_tag("!", _Content, _State) ->
"[]".
template_path(Mod) ->
ModPath = code:which(Mod),
re:replace(ModPath, "\.beam$", ".mustache", [{return, list}]).
get(Key, Ctx) when is_list(Key) ->
{ok, Mod} = dict:find('__mod__', Ctx),
get(list_to_atom(Key), Ctx, Mod);
get(Key, Ctx) ->
{ok, Mod} = dict:find('__mod__', Ctx),
get(Key, Ctx, Mod).
get(Key, Ctx, Mod) when is_list(Key) ->
get(list_to_atom(Key), Ctx, Mod);
get(Key, Ctx, Mod) ->
case dict:find(Key, Ctx) of
{ok, Val} ->
% io:format("From Ctx {~p, ~p}~n", [Key, Val]),
to_s(Val);
error ->
case erlang:function_exported(Mod, Key, 1) of
true ->
Val = to_s(Mod:Key(Ctx)),
% io:format("From Mod/1 {~p, ~p}~n", [Key, Val]),
Val;
false ->
case erlang:function_exported(Mod, Key, 0) of
true ->
Val = to_s(Mod:Key()),
% io:format("From Mod/0 {~p, ~p}~n", [Key, Val]),
Val;
false ->
[]
end
end
end.
to_s(Val) when is_integer(Val) ->
integer_to_list(Val);
to_s(Val) when is_float(Val) ->
io_lib:format("~.2f", [Val]);
to_s(Val) when is_atom(Val) ->
atom_to_list(Val);
to_s(Val) ->
Val.
escape(HTML) ->
escape(HTML, []).
escape([], Acc) ->
lists:reverse(Acc);
escape(["<" | Rest], Acc) ->
escape(Rest, lists:reverse("<", Acc));
escape([">" | Rest], Acc) ->
escape(Rest, lists:reverse(">", Acc));
escape(["&" | Rest], Acc) ->
escape(Rest, lists:reverse("&", Acc));
escape([X | Rest], Acc) ->
escape(Rest, [X | Acc]).
%%---------------------------------------------------------------------------
start([T]) ->
Out = render(list_to_atom(T)),
io:format(Out ++ "~n", []).
-ifdef(TEST).
simple_test() ->
Ctx = dict:from_list([{name, "world"}]),
Result = render("Hello {{name}}!", Ctx),
?assertEqual("Hello world!", Result).
integer_values_too_test() ->
Ctx = dict:from_list([{name, "Chris"}, {value, 10000}]),
Result = render("Hello {{name}}~nYou have just won ${{value}}!", Ctx),
?assertEqual("Hello Chris~nYou have just won $10000!", Result).
-endif.