-module(solid_parser).
-export([parse/1,file/1]).
-define(p_anything,true).
-define(p_charclass,true).
-define(p_choose,true).
-define(p_label,true).
-define(p_not,true).
-define(p_one_or_more,true).
-define(p_optional,true).
-define(p_scan,true).
-define(p_seq,true).
-define(p_string,true).
-define(p_zero_or_more,true).



-spec file(file:name()) -> any().
file(Filename) -> case file:read_file(Filename) of {ok,Bin} -> parse(Bin); Err -> Err end.

-spec parse(binary() | list()) -> any().
parse(List) when is_list(List) -> parse(unicode:characters_to_binary(List));
parse(Input) when is_binary(Input) ->
  _ = setup_memo(),
  Result = case 'text'(Input,{{line,1},{column,1}}) of
             {AST, <<>>, _Index} -> AST;
             Any -> Any
           end,
  release_memo(), Result.

-spec 'text'(input(), index()) -> parse_result().
'text'(Input, Index) ->
  p(Input, Index, 'text', fun(I,D) -> (p_seq([p_label('string', fun 'blob'/2), p_optional(p_choose([p_seq([p_label('object', fun 'object'/2), p_label('text', fun 'text'/2)]), p_seq([p_label('tag', fun 'tag'/2), p_label('text', fun 'text'/2)]), p_seq([p_label('open_object', fun 'open_object'/2), p_label('text', fun 'text'/2)])]))]))(I,D) end, fun(Node, _Idx) ->Node end).

-spec 'blob'(input(), index()) -> parse_result().
'blob'(Input, Index) ->
  p(Input, Index, 'blob', fun(I,D) -> (p_zero_or_more(p_seq([p_not(fun 'open_object'/2), p_not(fun 'open_tag'/2), p_anything()])))(I,D) end, fun(Node, _Idx) ->iolist_to_binary(Node) end).

-spec 'object'(input(), index()) -> parse_result().
'object'(Input, Index) ->
  p(Input, Index, 'object', fun(I,D) -> (p_seq([p_label('open_object', fun 'open_object'/2), fun 'space'/2, p_optional(p_choose([p_seq([p_label('argument', fun 'argument'/2), p_label('filters', fun 'filters'/2)]), p_label('argument', fun 'argument'/2)])), fun 'space'/2, p_label('close_object', fun 'close_object'/2)]))(I,D) end, fun(Node, _Idx) ->
case Node of
  [_, _, Block, _, _] -> lists:flatten([Block])
end
 end).

-spec 'tag'(input(), index()) -> parse_result().
'tag'(Input, Index) ->
  p(Input, Index, 'tag', fun(I,D) -> (p_choose([fun 'cond_if_tag'/2, fun 'cond_unless_tag'/2, fun 'cond_case_tag'/2, fun 'assign_tag'/2]))(I,D) end, fun(Node, _Idx) ->Node end).

-spec 'assign_tag'(input(), index()) -> parse_result().
'assign_tag'(Input, Index) ->
  p(Input, Index, 'assign_tag', fun(I,D) -> (p_seq([fun 'open_tag'/2, fun 'space'/2, fun 'assign'/2, fun 'space'/2, fun 'field'/2, fun 'space'/2, p_string(<<"=">>), fun 'space'/2, fun 'argument'/2, fun 'space'/2, fun 'close_tag'/2]))(I,D) end, fun(Node, _Idx) ->
case Node of
  [_, _, _, _, Field, _, _, _, Argument, _, _] -> {assign_exp, Field, Argument}
end
 end).

-spec 'cond_case_tag'(input(), index()) -> parse_result().
'cond_case_tag'(Input, Index) ->
  p(Input, Index, 'cond_case_tag', fun(I,D) -> (p_seq([fun 'case_tag'/2, p_one_or_more(fun 'when_tag'/2), p_optional(fun 'else_tag'/2), fun 'open_tag'/2, fun 'space'/2, fun 'endcase'/2, fun 'space'/2, fun 'close_tag'/2]))(I,D) end, fun(Node, _Idx) ->
case Node of
  [Case, Whens, Else, _, _, _, _, _] ->
    WhenMap = lists:foldl(fun({ Value, Text }, Map) -> maps:put(Value, Text, Map) end, #{}, Whens),
    [Case, {whens, WhenMap}, Else]
end
 end).

-spec 'case_tag'(input(), index()) -> parse_result().
'case_tag'(Input, Index) ->
  p(Input, Index, 'case_tag', fun(I,D) -> (p_seq([fun 'open_tag'/2, fun 'space'/2, fun 'case'/2, fun 'space'/2, fun 'argument'/2, fun 'space'/2, fun 'close_tag'/2, p_label('text', fun 'text'/2)]))(I,D) end, fun(Node, _Idx) ->
case Node of
  [_, _, _Case, _, Arg, _, _, _Text] -> {case_exp, [Arg]}
end
 end).

-spec 'when_tag'(input(), index()) -> parse_result().
'when_tag'(Input, Index) ->
  p(Input, Index, 'when_tag', fun(I,D) -> (p_seq([fun 'open_tag'/2, fun 'space'/2, fun 'when'/2, fun 'value'/2, fun 'close_tag'/2, p_label('text', fun 'text'/2)]))(I,D) end, fun(Node, _Idx) ->
case Node of
  [_, _, _When, Value, _, Text] -> { Value, [Text] }
end
 end).

-spec 'cond_if_tag'(input(), index()) -> parse_result().
'cond_if_tag'(Input, Index) ->
  p(Input, Index, 'cond_if_tag', fun(I,D) -> (p_seq([fun 'if_tag'/2, p_zero_or_more(fun 'elsif_tag'/2), p_optional(fun 'else_tag'/2), fun 'open_tag'/2, fun 'space'/2, fun 'endif'/2, fun 'space'/2, fun 'close_tag'/2]))(I,D) end, fun(Node, _Idx) ->
case Node of
  [IfExp, [], [], _, _, _EndIf, _, _] -> [IfExp];
  [IfExp, [], ElseExp, _, _, _EndIf, _, _] -> [IfExp, ElseExp];
  [IfExp, Elsifs, [], _, _, _EndIf, _, _] -> [IfExp, {elsif_exps, Elsifs}];
  [IfExp, Elsifs, ElseExp, _, _, _EndIf, _, _] -> [IfExp, Elsifs, ElseExp]
end
 end).

-spec 'if_tag'(input(), index()) -> parse_result().
'if_tag'(Input, Index) ->
  p(Input, Index, 'if_tag', fun(I,D) -> (p_seq([fun 'open_tag'/2, fun 'space'/2, fun 'if'/2, p_label('expression', fun 'boolean_expression'/2), fun 'close_tag'/2, p_label('text', fun 'text'/2)]))(I,D) end, fun(Node, _Idx) ->
case Node of
  [_, _, _If, Exp, _, Text] -> {if_exp, [Exp, Text]}
end
 end).

-spec 'elsif_tag'(input(), index()) -> parse_result().
'elsif_tag'(Input, Index) ->
  p(Input, Index, 'elsif_tag', fun(I,D) -> (p_seq([fun 'open_tag'/2, fun 'space'/2, fun 'elsif'/2, p_label('expression', fun 'boolean_expression'/2), fun 'close_tag'/2, p_label('text', fun 'text'/2)]))(I,D) end, fun(Node, _Idx) ->
case Node of
  [_, _, _Elsif, Exp, _, Text] -> {elsif_exp, [Exp, Text]}
end
 end).

-spec 'else_tag'(input(), index()) -> parse_result().
'else_tag'(Input, Index) ->
  p(Input, Index, 'else_tag', fun(I,D) -> (p_seq([fun 'open_tag'/2, fun 'space'/2, fun 'else'/2, fun 'space'/2, fun 'close_tag'/2, p_label('text', fun 'text'/2)]))(I,D) end, fun(Node, _Idx) ->
case Node of
  [_, _, _Else, _, _, ElseText] -> {else_exp, [ElseText]}
end
 end).

-spec 'unless_tag'(input(), index()) -> parse_result().
'unless_tag'(Input, Index) ->
  p(Input, Index, 'unless_tag', fun(I,D) -> (p_seq([fun 'open_tag'/2, fun 'space'/2, fun 'unless'/2, p_label('expression', fun 'boolean_expression'/2), fun 'close_tag'/2, p_label('text', fun 'text'/2)]))(I,D) end, fun(Node, _Idx) ->
case Node of
  [_, _, _Unless, Exp, _, Text] -> {unless_exp, [Exp, Text]}
end
 end).

-spec 'cond_unless_tag'(input(), index()) -> parse_result().
'cond_unless_tag'(Input, Index) ->
  p(Input, Index, 'cond_unless_tag', fun(I,D) -> (p_seq([fun 'unless_tag'/2, p_zero_or_more(fun 'elsif_tag'/2), p_optional(fun 'else_tag'/2), fun 'open_tag'/2, fun 'space'/2, fun 'endunless'/2, fun 'space'/2, fun 'close_tag'/2]))(I,D) end, fun(Node, _Idx) ->
case Node of
  [UnlessExp, [], _, _, _EndUnless, _, _] -> [UnlessExp];
  [UnlessExp, [], ElseExp, _, _, _EndUnless, _, _] -> [UnlessExp, ElseExp];
  [UnlessExp, Elsifs, [], _, _, _EndUnless, _, _] -> [UnlessExp, {elsif_exps, Elsifs}];
  [UnlessExp, Elsifs, ElseExp, _, _, _EndUnless, _, _] -> [UnlessExp, Elsifs, ElseExp]
end
 end).

-spec 'expression'(input(), index()) -> parse_result().
'expression'(Input, Index) ->
  p(Input, Index, 'expression', fun(I,D) -> (p_seq([fun 'space'/2, p_choose([p_seq([fun 'argument'/2, fun 'space'/2, fun 'operator'/2, fun 'space'/2, fun 'argument'/2]), fun 'boolean'/2]), fun 'space'/2]))(I,D) end, fun(Node, _Idx) ->
case Node of
  [_, [Arg1, _, Op, _, Arg2], _] -> {Arg1, Op, Arg2};
  [_, Bool, _] -> Bool
end
 end).

-spec 'boolean_expression'(input(), index()) -> parse_result().
'boolean_expression'(Input, Index) ->
  p(Input, Index, 'boolean_expression', fun(I,D) -> (p_seq([fun 'expression'/2, p_zero_or_more(p_seq([p_choose([fun 'and'/2, fun 'or'/2]), fun 'expression'/2]))]))(I,D) end, fun(Node, _Idx) ->
case Node of
  [Exp, Exps] -> [Exp | Exps]
end
 end).

-spec 'filters'(input(), index()) -> parse_result().
'filters'(Input, Index) ->
  p(Input, Index, 'filters', fun(I,D) -> (p_one_or_more(p_seq([fun 'space'/2, p_string(<<"|">>), fun 'space'/2, fun 'filter'/2, p_optional(p_seq([p_string(<<":">>), fun 'space'/2, fun 'arguments'/2]))])))(I,D) end, fun(Node, _Idx) ->
[case N of
  [_, _, _, Filter, [_, _, Args]] -> {Filter, Args};
  [_, _, _, Filter, _] -> {Filter, []}
end || N <- Node]
 end).

-spec 'arguments'(input(), index()) -> parse_result().
'arguments'(Input, Index) ->
  p(Input, Index, 'arguments', fun(I,D) -> (p_seq([fun 'argument'/2, p_zero_or_more(p_seq([fun 'space'/2, p_string(<<",">>), fun 'space'/2, fun 'argument'/2]))]))(I,D) end, fun(Node, _Idx) ->
case Node of
  [Arg1, Args] -> [Arg1 | [Arg || [_, _, _, Arg] <- Args]]
end
 end).

-spec 'argument'(input(), index()) -> parse_result().
'argument'(Input, Index) ->
  p(Input, Index, 'argument', fun(I,D) -> (p_choose([p_label('value', fun 'value'/2), fun 'field'/2]))(I,D) end, fun(Node, _Idx) ->Node end).

-spec 'field'(input(), index()) -> parse_result().
'field'(Input, Index) ->
  p(Input, Index, 'field', fun(I,D) -> (p_seq([p_zero_or_more(p_charclass(<<"[0-9a-zA-Z\.]">>)), p_zero_or_more(fun 'access'/2)]))(I,D) end, fun(Node, _Idx) ->
 case Node of
   [FieldName | [[]]] -> {field, iolist_to_binary(FieldName)};
   [FieldName | [Accesses]] ->
     {field, iolist_to_binary(FieldName), Accesses}
 end
 end).

-spec 'access'(input(), index()) -> parse_result().
'access'(Input, Index) ->
  p(Input, Index, 'access', fun(I,D) -> (p_seq([p_string(<<"[">>), fun 'int'/2, p_string(<<"]">>)]))(I,D) end, fun(Node, _Idx) ->
case Node of
  [_, Integer, _] -> {access, list_to_integer(binary_to_list(iolist_to_binary(Integer)))}
end
 end).

-spec 'value'(input(), index()) -> parse_result().
'value'(Input, Index) ->
  p(Input, Index, 'value', fun(I,D) -> (p_seq([fun 'space'/2, p_choose([fun 'string'/2, fun 'number'/2, fun 'true'/2, fun 'false'/2, fun 'null'/2]), fun 'space'/2]))(I,D) end, fun(Node, _Idx) ->lists:nth(2, Node) end).

-spec 'string'(input(), index()) -> parse_result().
'string'(Input, Index) ->
  p(Input, Index, 'string', fun(I,D) -> (p_choose([fun 'single_quoted_string'/2, fun 'double_quoted_string'/2]))(I,D) end, fun(Node, _Idx) ->
iolist_to_binary(proplists:get_value(string, Node))
 end).

-spec 'operator'(input(), index()) -> parse_result().
'operator'(Input, Index) ->
  p(Input, Index, 'operator', fun(I,D) -> (p_choose([p_string(<<"==">>), p_string(<<"!=">>), p_string(<<">=">>), p_string(<<"<=">>), p_string(<<">">>), p_string(<<"<">>), p_string(<<"contains">>)]))(I,D) end, fun(Node, _Idx) ->
  binary_to_existing_atom(Node, utf8)
 end).

-spec 'open_object'(input(), index()) -> parse_result().
'open_object'(Input, Index) ->
  p(Input, Index, 'open_object', fun(I,D) -> (p_string(<<"{{">>))(I,D) end, fun(Node, _Idx) ->Node end).

-spec 'close_object'(input(), index()) -> parse_result().
'close_object'(Input, Index) ->
  p(Input, Index, 'close_object', fun(I,D) -> (p_string(<<"}}">>))(I,D) end, fun(Node, _Idx) ->Node end).

-spec 'open_tag'(input(), index()) -> parse_result().
'open_tag'(Input, Index) ->
  p(Input, Index, 'open_tag', fun(I,D) -> (p_string(<<"{%">>))(I,D) end, fun(Node, _Idx) ->Node end).

-spec 'close_tag'(input(), index()) -> parse_result().
'close_tag'(Input, Index) ->
  p(Input, Index, 'close_tag', fun(I,D) -> (p_string(<<"%}">>))(I,D) end, fun(Node, _Idx) ->Node end).

-spec 'if'(input(), index()) -> parse_result().
'if'(Input, Index) ->
  p(Input, Index, 'if', fun(I,D) -> (p_string(<<"if">>))(I,D) end, fun(Node, _Idx) ->Node end).

-spec 'else'(input(), index()) -> parse_result().
'else'(Input, Index) ->
  p(Input, Index, 'else', fun(I,D) -> (p_string(<<"else">>))(I,D) end, fun(Node, _Idx) ->Node end).

-spec 'elsif'(input(), index()) -> parse_result().
'elsif'(Input, Index) ->
  p(Input, Index, 'elsif', fun(I,D) -> (p_string(<<"elsif">>))(I,D) end, fun(Node, _Idx) ->Node end).

-spec 'endif'(input(), index()) -> parse_result().
'endif'(Input, Index) ->
  p(Input, Index, 'endif', fun(I,D) -> (p_string(<<"endif">>))(I,D) end, fun(Node, _Idx) ->Node end).

-spec 'unless'(input(), index()) -> parse_result().
'unless'(Input, Index) ->
  p(Input, Index, 'unless', fun(I,D) -> (p_string(<<"unless">>))(I,D) end, fun(Node, _Idx) ->Node end).

-spec 'endunless'(input(), index()) -> parse_result().
'endunless'(Input, Index) ->
  p(Input, Index, 'endunless', fun(I,D) -> (p_string(<<"endunless">>))(I,D) end, fun(Node, _Idx) ->Node end).

-spec 'case'(input(), index()) -> parse_result().
'case'(Input, Index) ->
  p(Input, Index, 'case', fun(I,D) -> (p_string(<<"case">>))(I,D) end, fun(Node, _Idx) ->Node end).

-spec 'when'(input(), index()) -> parse_result().
'when'(Input, Index) ->
  p(Input, Index, 'when', fun(I,D) -> (p_string(<<"when">>))(I,D) end, fun(Node, _Idx) ->Node end).

-spec 'endcase'(input(), index()) -> parse_result().
'endcase'(Input, Index) ->
  p(Input, Index, 'endcase', fun(I,D) -> (p_string(<<"endcase">>))(I,D) end, fun(Node, _Idx) ->Node end).

-spec 'assign'(input(), index()) -> parse_result().
'assign'(Input, Index) ->
  p(Input, Index, 'assign', fun(I,D) -> (p_string(<<"assign">>))(I,D) end, fun(Node, _Idx) ->Node end).

-spec 'filter'(input(), index()) -> parse_result().
'filter'(Input, Index) ->
  p(Input, Index, 'filter', fun(I,D) -> (p_zero_or_more(p_charclass(<<"[a-zA-Z]">>)))(I,D) end, fun(Node, _Idx) ->iolist_to_binary(Node) end).

-spec 'space'(input(), index()) -> parse_result().
'space'(Input, Index) ->
  p(Input, Index, 'space', fun(I,D) -> (p_zero_or_more(p_charclass(<<"[\s\t\n\s\r]">>)))(I,D) end, fun(Node, _Idx) ->{space, iolist_to_binary(Node)} end).

-spec 'double_quoted_string'(input(), index()) -> parse_result().
'double_quoted_string'(Input, Index) ->
  p(Input, Index, 'double_quoted_string', fun(I,D) -> (p_seq([p_string(<<"\"">>), p_label('string', p_zero_or_more(p_seq([p_not(p_string(<<"\"">>)), p_choose([p_string(<<"\\\\">>), p_string(<<"\\\"">>), p_anything()])]))), p_string(<<"\"">>)]))(I,D) end, fun(Node, _Idx) ->Node end).

-spec 'single_quoted_string'(input(), index()) -> parse_result().
'single_quoted_string'(Input, Index) ->
  p(Input, Index, 'single_quoted_string', fun(I,D) -> (p_seq([p_string(<<"\'">>), p_label('string', p_zero_or_more(p_seq([p_not(p_string(<<"\'">>)), p_choose([p_string(<<"\\\\">>), p_string(<<"\\\'">>), p_anything()])]))), p_string(<<"\'">>)]))(I,D) end, fun(Node, _Idx) ->Node end).

-spec 'number'(input(), index()) -> parse_result().
'number'(Input, Index) ->
  p(Input, Index, 'number', fun(I,D) -> (p_seq([fun 'int'/2, p_optional(fun 'frac'/2), p_optional(fun 'exp'/2)]))(I,D) end, fun(Node, _Idx) ->
case Node of
  [Int, [], []] -> list_to_integer(binary_to_list(iolist_to_binary(Int)));
  [Int, Frac, []] -> list_to_float(binary_to_list(iolist_to_binary([Int, Frac])));
  [Int, [], Exp] -> list_to_float(binary_to_list(iolist_to_binary([Int, ".0", Exp])));
  _ -> list_to_float(binary_to_list(iolist_to_binary(Node)))
end
 end).

-spec 'int'(input(), index()) -> parse_result().
'int'(Input, Index) ->
  p(Input, Index, 'int', fun(I,D) -> (p_seq([p_optional(p_string(<<"-">>)), p_choose([p_seq([fun 'non_zero_digit'/2, p_one_or_more(fun 'digit'/2)]), fun 'digit'/2])]))(I,D) end, fun(Node, _Idx) ->Node end).

-spec 'frac'(input(), index()) -> parse_result().
'frac'(Input, Index) ->
  p(Input, Index, 'frac', fun(I,D) -> (p_seq([p_string(<<".">>), p_one_or_more(fun 'digit'/2)]))(I,D) end, fun(Node, _Idx) ->Node end).

-spec 'exp'(input(), index()) -> parse_result().
'exp'(Input, Index) ->
  p(Input, Index, 'exp', fun(I,D) -> (p_seq([fun 'e'/2, p_one_or_more(fun 'digit'/2)]))(I,D) end, fun(Node, _Idx) ->Node end).

-spec 'e'(input(), index()) -> parse_result().
'e'(Input, Index) ->
  p(Input, Index, 'e', fun(I,D) -> (p_seq([p_charclass(<<"[eE]">>), p_optional(p_choose([p_string(<<"+">>), p_string(<<"-">>)]))]))(I,D) end, fun(Node, _Idx) ->Node end).

-spec 'non_zero_digit'(input(), index()) -> parse_result().
'non_zero_digit'(Input, Index) ->
  p(Input, Index, 'non_zero_digit', fun(I,D) -> (p_charclass(<<"[1-9]">>))(I,D) end, fun(Node, _Idx) ->Node end).

-spec 'digit'(input(), index()) -> parse_result().
'digit'(Input, Index) ->
  p(Input, Index, 'digit', fun(I,D) -> (p_charclass(<<"[0-9]">>))(I,D) end, fun(Node, _Idx) ->Node end).

-spec 'boolean'(input(), index()) -> parse_result().
'boolean'(Input, Index) ->
  p(Input, Index, 'boolean', fun(I,D) -> (p_choose([fun 'true'/2, fun 'false'/2]))(I,D) end, fun(Node, _Idx) ->Node end).

-spec 'true'(input(), index()) -> parse_result().
'true'(Input, Index) ->
  p(Input, Index, 'true', fun(I,D) -> (p_string(<<"true">>))(I,D) end, fun(_Node, _Idx) ->true end).

-spec 'false'(input(), index()) -> parse_result().
'false'(Input, Index) ->
  p(Input, Index, 'false', fun(I,D) -> (p_string(<<"false">>))(I,D) end, fun(_Node, _Idx) ->false end).

-spec 'null'(input(), index()) -> parse_result().
'null'(Input, Index) ->
  p(Input, Index, 'null', fun(I,D) -> (p_string(<<"nil">>))(I,D) end, fun(_Node, _Idx) ->nil end).

-spec 'and'(input(), index()) -> parse_result().
'and'(Input, Index) ->
  p(Input, Index, 'and', fun(I,D) -> (p_string(<<"and">>))(I,D) end, fun(_Node, _Idx) ->bool_and end).

-spec 'or'(input(), index()) -> parse_result().
'or'(Input, Index) ->
  p(Input, Index, 'or', fun(I,D) -> (p_string(<<"or">>))(I,D) end, fun(_Node, _Idx) ->bool_or end).



-file("peg_includes.hrl", 1).
-type index() :: {{line, pos_integer()}, {column, pos_integer()}}.
-type input() :: binary().
-type parse_failure() :: {fail, term()}.
-type parse_success() :: {term(), input(), index()}.
-type parse_result() :: parse_failure() | parse_success().
-type parse_fun() :: fun((input(), index()) -> parse_result()).
-type xform_fun() :: fun((input(), index()) -> term()).

-spec p(input(), index(), atom(), parse_fun(), xform_fun()) -> parse_result().
p(Inp, StartIndex, Name, ParseFun, TransformFun) ->
  case get_memo(StartIndex, Name) of      % See if the current reduction is memoized
    {ok, Memo} -> %Memo;                     % If it is, return the stored result
      Memo;
    _ ->                                        % If not, attempt to parse
      Result = case ParseFun(Inp, StartIndex) of
        {fail,_} = Failure ->                       % If it fails, memoize the failure
          Failure;
        {Match, InpRem, NewIndex} ->               % If it passes, transform and memoize the result.
          Transformed = TransformFun(Match, StartIndex),
          {Transformed, InpRem, NewIndex}
      end,
      memoize(StartIndex, Name, Result),
      Result
  end.

-spec setup_memo() -> ets:tid().
setup_memo() ->
  put({parse_memo_table, ?MODULE}, ets:new(?MODULE, [set])).

-spec release_memo() -> true.
release_memo() ->
  ets:delete(memo_table_name()).

-spec memoize(index(), atom(), parse_result()) -> true.
memoize(Index, Name, Result) ->
  Memo = case ets:lookup(memo_table_name(), Index) of
              [] -> [];
              [{Index, Plist}] -> Plist
         end,
  ets:insert(memo_table_name(), {Index, [{Name, Result}|Memo]}).

-spec get_memo(index(), atom()) -> {ok, term()} | {error, not_found}.
get_memo(Index, Name) ->
  case ets:lookup(memo_table_name(), Index) of
    [] -> {error, not_found};
    [{Index, Plist}] ->
      case proplists:lookup(Name, Plist) of
        {Name, Result}  -> {ok, Result};
        _  -> {error, not_found}
      end
    end.

-spec memo_table_name() -> ets:tid().
memo_table_name() ->
    get({parse_memo_table, ?MODULE}).

-ifdef(p_eof).
-spec p_eof() -> parse_fun().
p_eof() ->
  fun(<<>>, Index) -> {eof, [], Index};
     (_, Index) -> {fail, {expected, eof, Index}} end.
-endif.

-ifdef(p_optional).
-spec p_optional(parse_fun()) -> parse_fun().
p_optional(P) ->
  fun(Input, Index) ->
      case P(Input, Index) of
        {fail,_} -> {[], Input, Index};
        {_, _, _} = Success -> Success
      end
  end.
-endif.

-ifdef(p_not).
-spec p_not(parse_fun()) -> parse_fun().
p_not(P) ->
  fun(Input, Index)->
      case P(Input,Index) of
        {fail,_} ->
          {[], Input, Index};
        {Result, _, _} -> {fail, {expected, {no_match, Result},Index}}
      end
  end.
-endif.

-ifdef(p_assert).
-spec p_assert(parse_fun()) -> parse_fun().
p_assert(P) ->
  fun(Input,Index) ->
      case P(Input,Index) of
        {fail,_} = Failure-> Failure;
        _ -> {[], Input, Index}
      end
  end.
-endif.

-ifdef(p_seq).
-spec p_seq([parse_fun()]) -> parse_fun().
p_seq(P) ->
  fun(Input, Index) ->
      p_all(P, Input, Index, [])
  end.

-spec p_all([parse_fun()], input(), index(), [term()]) -> parse_result().
p_all([], Inp, Index, Accum ) -> {lists:reverse( Accum ), Inp, Index};
p_all([P|Parsers], Inp, Index, Accum) ->
  case P(Inp, Index) of
    {fail, _} = Failure -> Failure;
    {Result, InpRem, NewIndex} -> p_all(Parsers, InpRem, NewIndex, [Result|Accum])
  end.
-endif.

-ifdef(p_choose).
-spec p_choose([parse_fun()]) -> parse_fun().
p_choose(Parsers) ->
  fun(Input, Index) ->
      p_attempt(Parsers, Input, Index, none)
  end.

-spec p_attempt([parse_fun()], input(), index(), none | parse_failure()) -> parse_result().
p_attempt([], _Input, _Index, Failure) -> Failure;
p_attempt([P|Parsers], Input, Index, FirstFailure)->
  case P(Input, Index) of
    {fail, _} = Failure ->
      case FirstFailure of
        none -> p_attempt(Parsers, Input, Index, Failure);
        _ -> p_attempt(Parsers, Input, Index, FirstFailure)
      end;
    Result -> Result
  end.
-endif.

-ifdef(p_zero_or_more).
-spec p_zero_or_more(parse_fun()) -> parse_fun().
p_zero_or_more(P) ->
  fun(Input, Index) ->
      p_scan(P, Input, Index, [])
  end.
-endif.

-ifdef(p_one_or_more).
-spec p_one_or_more(parse_fun()) -> parse_fun().
p_one_or_more(P) ->
  fun(Input, Index)->
      Result = p_scan(P, Input, Index, []),
      case Result of
        {[_|_], _, _} ->
          Result;
        _ ->
          {fail, {expected, Failure, _}} = P(Input,Index),
          {fail, {expected, {at_least_one, Failure}, Index}}
      end
  end.
-endif.

-ifdef(p_label).
-spec p_label(atom(), parse_fun()) -> parse_fun().
p_label(Tag, P) ->
  fun(Input, Index) ->
      case P(Input, Index) of
        {fail,_} = Failure ->
           Failure;
        {Result, InpRem, NewIndex} ->
          {{Tag, Result}, InpRem, NewIndex}
      end
  end.
-endif.

-ifdef(p_scan).
-spec p_scan(parse_fun(), input(), index(), [term()]) -> {[term()], input(), index()}.
p_scan(_, <<>>, Index, Accum) -> {lists:reverse(Accum), <<>>, Index};
p_scan(P, Inp, Index, Accum) ->
  case P(Inp, Index) of
    {fail,_} -> {lists:reverse(Accum), Inp, Index};
    {Result, InpRem, NewIndex} -> p_scan(P, InpRem, NewIndex, [Result | Accum])
  end.
-endif.

-ifdef(p_string).
-spec p_string(binary()) -> parse_fun().
p_string(S) ->
    Length = erlang:byte_size(S),
    fun(Input, Index) ->
      try
          <<S:Length/binary, Rest/binary>> = Input,
          {S, Rest, p_advance_index(S, Index)}
      catch
          error:{badmatch,_} -> {fail, {expected, {string, S}, Index}}
      end
    end.
-endif.

-ifdef(p_anything).
-spec p_anything() -> parse_fun().
p_anything() ->
  fun(<<>>, Index) -> {fail, {expected, any_character, Index}};
     (Input, Index) when is_binary(Input) ->
          <<C/utf8, Rest/binary>> = Input,
          {<<C/utf8>>, Rest, p_advance_index(<<C/utf8>>, Index)}
  end.
-endif.

-ifdef(p_charclass).
-spec p_charclass(string() | binary()) -> parse_fun().
p_charclass(Class) ->
    {ok, RE} = re:compile(Class, [unicode, dotall]),
    fun(Inp, Index) ->
            case re:run(Inp, RE, [anchored]) of
                {match, [{0, Length}|_]} ->
                    {Head, Tail} = erlang:split_binary(Inp, Length),
                    {Head, Tail, p_advance_index(Head, Index)};
                _ -> {fail, {expected, {character_class, binary_to_list(Class)}, Index}}
            end
    end.
-endif.

-ifdef(p_regexp).
-spec p_regexp(binary()) -> parse_fun().
p_regexp(Regexp) ->
    {ok, RE} = re:compile(Regexp, [unicode, dotall, anchored]),
    fun(Inp, Index) ->
        case re:run(Inp, RE) of
            {match, [{0, Length}|_]} ->
                {Head, Tail} = erlang:split_binary(Inp, Length),
                {Head, Tail, p_advance_index(Head, Index)};
            _ -> {fail, {expected, {regexp, binary_to_list(Regexp)}, Index}}
        end
    end.
-endif.

-ifdef(line).
-spec line(index() | term()) -> pos_integer() | undefined.
line({{line,L},_}) -> L;
line(_) -> undefined.
-endif.

-ifdef(column).
-spec column(index() | term()) -> pos_integer() | undefined.
column({_,{column,C}}) -> C;
column(_) -> undefined.
-endif.

-spec p_advance_index(input() | unicode:charlist() | pos_integer(), index()) -> index().
p_advance_index(MatchedInput, Index) when is_list(MatchedInput) orelse is_binary(MatchedInput)-> % strings
  lists:foldl(fun p_advance_index/2, Index, unicode:characters_to_list(MatchedInput));
p_advance_index(MatchedInput, Index) when is_integer(MatchedInput) -> % single characters
  {{line, Line}, {column, Col}} = Index,
  case MatchedInput of
    $\n -> {{line, Line+1}, {column, 1}};
    _ -> {{line, Line}, {column, Col+1}}
  end.