Adding mustache.erl from http://github.com/mojombo/mustache.erl

src/mustache.erl

@@ -0,0 +1,219 @@
+%% 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}).
+
+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),
+  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(apply(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(apply(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_boolean(Val) ->
+  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("&lt;", Acc));
+escape([">" | Rest], Acc) ->
+  escape(Rest, lists:reverse("&gt;", Acc));
+escape(["&" | Rest], Acc) ->
+  escape(Rest, lists:reverse("&amp;", Acc));
+escape([X | Rest], Acc) ->
+  escape(Rest, [X | Acc]).
+
+%%---------------------------------------------------------------------------
+
+start([T]) ->
+  Out = render(list_to_atom(T)),
+  io:format(Out ++ "~n", []).
+