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%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 1996-2009. All Rights Reserved.
%%
%% 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 online 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.
%%
%% %CopyrightEnd%
%%
%% This is the syntax (metagrammar) of grammar definitions of the yecc
%% parser generator.
Nonterminals
grammar declaration rule head symbol symbols strings attached_code
token tokens.
Terminals
atom float integer reserved_symbol reserved_word string char var
'->' ':' dot.
Rootsymbol grammar.
grammar -> declaration : '$1'.
grammar -> rule : '$1'.
declaration -> symbol symbols dot: {'$1', '$2'}.
declaration -> symbol strings dot: {'$1', '$2'}.
rule -> head '->' symbols attached_code dot: {rule, ['$1' | '$3'], '$4'}.
head -> symbol : '$1'.
symbols -> symbol : ['$1'].
symbols -> symbol symbols : ['$1' | '$2'].
strings -> string : ['$1'].
strings -> string strings : ['$1' | '$2'].
attached_code -> ':' tokens : {erlang_code, '$2'}.
attached_code -> '$empty' : {erlang_code, [{atom, 0, '$undefined'}]}.
tokens -> token : ['$1'].
tokens -> token tokens : ['$1' | '$2'].
symbol -> var : symbol('$1').
symbol -> atom : symbol('$1').
symbol -> integer : symbol('$1').
symbol -> reserved_word : symbol('$1').
token -> var : '$1'.
token -> atom : '$1'.
token -> float : '$1'.
token -> integer : '$1'.
token -> string : '$1'.
token -> char : '$1'.
token -> reserved_symbol : {value_of('$1'), line_of('$1')}.
token -> reserved_word : {value_of('$1'), line_of('$1')}.
token -> '->' : {'->', line_of('$1')}. % Have to be treated in this
token -> ':' : {':', line_of('$1')}. % manner, because they are also
% special symbols of the metagrammar
Erlang code.
-record(symbol, {line, name}).
symbol(Symbol) ->
#symbol{line = line_of(Symbol), name = value_of(Symbol)}.
value_of(Token) ->
element(3, Token).
line_of(Token) ->
element(2, Token).
|
