erl_parse.erl

来自「OTP是开放电信平台的简称」· ERL 代码 · 共 1,387 行 · 第 1/5 页

    {'fun',Line,{clauses,check_clauses(Cs, 'fun', Arity)}}.

check_clauses(Cs, Name, Arity) ->
     mapl(fun ({clause,L,N,As,G,B}) when N =:= Name, length(As) =:= Arity ->
		 {clause,L,As,G,B};
	     ({clause,L,_N,_As,_G,_B}) ->
		 return_error(L, "head mismatch") end, Cs).

build_try(L,Es,Scs,{Ccs,As}) ->
    {'try',L,Es,Scs,Ccs,As}.

%% mapl(F,List)
%% an alternative map which always maps from left to right
%% and makes it possible to interrupt the mapping with throw on
%% the first occurence from left as expected.
%% can be removed when the jam machine (and all other machines)
%% uses the standardized (Erlang 5.0) evaluation order (from left to right)
mapl(F, [H|T]) ->
	V = F(H),
	[V | mapl(F,T)];
mapl(_, []) ->
	[].

%% normalise(AbsTerm)
%% abstract(Term)
%%  Convert between the abstract form of a term and a term.

normalise({char,_,C}) -> C;
normalise({integer,_,I}) -> I;
normalise({float,_,F}) -> F;
normalise({atom,_,A}) -> A;
normalise({string,_,S}) -> S;
normalise({nil,_}) -> [];
normalise({bin,_,Fs}) ->
    {value, B, _} =
	eval_bits:expr_grp(Fs, [],
			   fun(E, _) ->
				   {value, normalise(E), []}
			   end, [], true),
    B;
normalise({cons,_,Head,Tail}) ->
    [normalise(Head)|normalise(Tail)];
normalise({tuple,_,Args}) ->
    list_to_tuple(normalise_list(Args));
%% Atom dot-notation, as in 'foo.bar.baz'
normalise({record_field,_,_,_}=A) ->
    case package_segments(A) of
	error -> erlang:fault({badarg, A});
	As -> list_to_atom(packages:concat(As))
    end;
%% Special case for unary +/-.
normalise({op,_,'+',{char,_,I}}) -> I;
normalise({op,_,'+',{integer,_,I}}) -> I;
normalise({op,_,'+',{float,_,F}}) -> F;
normalise({op,_,'-',{char,_,I}}) -> -I;		%Weird, but compatible!
normalise({op,_,'-',{integer,_,I}}) -> -I;
normalise({op,_,'-',{float,_,F}}) -> -F;
normalise(X) -> erlang:fault({badarg, X}).

normalise_list([H|T]) ->
    [normalise(H)|normalise_list(T)];
normalise_list([]) ->
    [].

abstract(T) when is_integer(T) -> {integer,0,T};
abstract(T) when is_float(T) -> {float,0,T};
abstract(T) when is_atom(T) -> {atom,0,T};
abstract([]) -> {nil,0};
abstract(B) when is_binary(B) ->
    {bin, 0, lists:map(fun(Byte) ->
			       {bin_element, 0,
				{integer, 0, Byte}, default, default}
		       end,
		       binary_to_list(B))};
abstract([C|T]) when is_integer(C), 0 =< C, C < 256 ->
    abstract_string(T, [C]);
abstract([H|T]) ->
    {cons,0,abstract(H),abstract(T)};
abstract(Tuple) when is_tuple(Tuple) ->
    {tuple,0,abstract_list(tuple_to_list(Tuple))}.

abstract_string([C|T], String) when is_integer(C), 0 =< C, C < 256 ->
    abstract_string(T, [C|String]);
abstract_string([], String) ->
    {string, 0, lists:reverse(String)};
abstract_string(T, String) ->
    not_string(String, abstract(T)).

not_string([C|T], Result) ->
    not_string(T, {cons, 0, {integer, 0, C}, Result});
not_string([], Result) ->
    Result.

abstract_list([H|T]) ->
    [abstract(H)|abstract_list(T)];
abstract_list([]) ->
    [].

%%% abstract/2 keeps the line number
abstract(T, Line) when is_integer(T) -> {integer,Line,T};
abstract(T, Line) when is_float(T) -> {float,Line,T};
abstract(T, Line) when is_atom(T) -> {atom,Line,T};
abstract([], Line) -> {nil,Line};
abstract(B, Line) when is_binary(B) ->
    {bin, Line, lists:map(fun(Byte) ->
			       {bin_element, Line,
				{integer, Line, Byte}, default, default}
		       end,
		       binary_to_list(B))};
abstract([C|T], Line) when is_integer(C), 0 =< C, C < 256 ->
    abstract_string(T, [C], Line);
abstract([H|T], Line) ->
    {cons,Line,abstract(H, Line),abstract(T, Line)};
abstract(Tuple, Line) when is_tuple(Tuple) ->
    {tuple,Line,abstract_list(tuple_to_list(Tuple), Line)}.

abstract_string([C|T], String, Line) when is_integer(C), 0 =< C, C < 256 ->
    abstract_string(T, [C|String], Line);
abstract_string([], String, Line) ->
    {string, Line, lists:reverse(String)};
abstract_string(T, String, Line) ->
    not_string(String, abstract(T, Line), Line).

not_string([C|T], Result, Line) ->
    not_string(T, {cons, Line, {integer, Line, C}, Result}, Line);
not_string([], Result, _Line) ->
    Result.

abstract_list([H|T], Line) ->
    [abstract(H, Line)|abstract_list(T, Line)];
abstract_list([], _Line) ->
    [].

%% tokens(AbsTerm) -> [Token]
%% tokens(AbsTerm, More) -> [Token]
%%  Generate a list of tokens representing the abstract term.

tokens(Abs) ->
    tokens(Abs, []).

tokens({char,L,C}, More) -> [{char,L,C}|More];
tokens({integer,L,N}, More) -> [{integer,L,N}|More];
tokens({float,L,F}, More) -> [{float,L,F}|More];
tokens({atom,L,A}, More) -> [{atom,L,A}|More];
tokens({var,L,V}, More) -> [{var,L,V}|More];
tokens({string,L,S}, More) -> [{string,L,S}|More];
tokens({nil,L}, More) -> [{'[',L},{']',L}|More];
tokens({cons,L,Head,Tail}, More) ->
    [{'[',L}|tokens(Head, tokens_tail(Tail, More))];
tokens({tuple,L,[]}, More) ->
    [{'{',L},{'}',L}|More];
tokens({tuple,L,[E|Es]}, More) ->
    [{'{',L}|tokens(E, tokens_tuple(Es, line(E), More))].

tokens_tail({cons,L,Head,Tail}, More) ->
    [{',',L}|tokens(Head, tokens_tail(Tail, More))];
tokens_tail({nil,L}, More) ->
    [{']',L}|More];
tokens_tail(Other, More) ->
    L = line(Other),
    [{'|',L}|tokens(Other, [{']',L}|More])].

tokens_tuple([E|Es], Line, More) ->
    [{',',Line}|tokens(E, tokens_tuple(Es, line(E), More))];
tokens_tuple([], Line, More) ->
    [{'}',Line}|More].

%% Give the relative precedences of operators.

inop_prec('=') -> {150,100,100};
inop_prec('!') -> {150,100,100};
inop_prec('orelse') -> {160,150,150};
inop_prec('andalso') -> {200,160,160};
inop_prec('==') -> {300,200,300};
inop_prec('/=') -> {300,200,300};
inop_prec('=<') -> {300,200,300};
inop_prec('<') -> {300,200,300};
inop_prec('>=') -> {300,200,300};
inop_prec('>') -> {300,200,300};
inop_prec('=:=') -> {300,200,300};
inop_prec('=/=') -> {300,200,300};
inop_prec('++') -> {400,300,300};
inop_prec('--') -> {400,300,300};
inop_prec('+') -> {400,400,500};
inop_prec('-') -> {400,400,500};
inop_prec('bor') -> {400,400,500};
inop_prec('bxor') -> {400,400,500};
inop_prec('bsl') -> {400,400,500};
inop_prec('bsr') -> {400,400,500};
inop_prec('or') -> {400,400,500};
inop_prec('xor') -> {400,400,500};
inop_prec('*') -> {500,500,600};
inop_prec('/') -> {500,500,600};
inop_prec('div') -> {500,500,600};
inop_prec('rem') -> {500,500,600};
inop_prec('band') -> {500,500,600};
inop_prec('and') -> {500,500,600};
inop_prec('#') -> {800,700,800};
inop_prec(':') -> {900,800,900};
inop_prec('.') -> {900,900,1000}.

preop_prec('catch') -> {0,100};
preop_prec('+') -> {600,700};
preop_prec('-') -> {600,700};
preop_prec('bnot') -> {600,700};
preop_prec('not') -> {600,700};
preop_prec('#') -> {700,800}.

func_prec() -> {800,700}.

max_prec() -> 1000.

-file("/ldisk/daily_build/otp_prebuild_r11b.2007-06-11_19/otp_src_R11B-5/bootstrap/lib/parsetools/include/yeccpre.hrl", 0).
%% ``The contents of this file are subject to the Erlang Public License,
%% Version 1.1, (the "License"); you may not use this file except in
%% compliance with the License. You should have received a copy of the
%% Erlang Public License along with this software. If not, it can be
%% retrieved via the world wide web at http://www.erlang.org/.
%% 
%% Software distributed under the License is distributed on an "AS IS"
%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
%% the License for the specific language governing rights and limitations
%% under the License.
%% 
%% The Initial Developer of the Original Code is Ericsson Utvecklings AB.
%% Portions created by Ericsson are Copyright 1999, Ericsson Utvecklings
%% AB. All Rights Reserved.''
%% 
%%     $Id $
%%

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% The parser generator will insert appropriate declarations before this line.%

parse(Tokens) ->
    yeccpars0(Tokens, false).

parse_and_scan({F, A}) -> % Fun or {M, F}
    yeccpars0([], {F, A});
parse_and_scan({M, F, A}) ->
    yeccpars0([], {{M, F}, A}).

format_error(Message) ->
    case io_lib:deep_char_list(Message) of
	true ->
	    Message;
	_ ->
	    io_lib:write(Message)
    end.

% To be used in grammar files to throw an error message to the parser
% toplevel. Doesn't have to be exported!
-compile({nowarn_unused_function,{return_error,2}}).
return_error(Line, Message) ->
    throw({error, {Line, ?MODULE, Message}}).

yeccpars0(Tokens, MFA) ->
    try yeccpars1(Tokens, MFA, 0, [], [])
    catch 
        throw: {error, {_Line, ?MODULE, _M}} = Error -> 
                   Error % probably from return_error/1
    end.

% Don't change yeccpars1/6 too much, it is called recursively by yeccpars2/8!
yeccpars1([Token | Tokens], Tokenizer, State, States, Vstack) ->
    yeccpars2(State, element(1, Token), States, Vstack, Token, Tokens,
	      Tokenizer);
yeccpars1([], {F, A}, State, States, Vstack) ->
    case apply(F, A) of
        {ok, Tokens, _Endline} ->
	    yeccpars1(Tokens, {F, A}, State, States, Vstack);
        {eof, _Endline} ->
            yeccpars1([], false, State, States, Vstack);
        {error, Descriptor, _Endline} ->
            {error, Descriptor}
    end;
yeccpars1([], false, State, States, Vstack) ->
    yeccpars2(State, '$end', States, Vstack, {'$end', 999999}, [], false).