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|
// This file is part of PyANTLR. See LICENSE.txt for license
// details..........Copyright (C) Wolfgang Haefelinger, 2004.
//
// $Id$
options {
language=Python;
}
class transform_p extends Parser;
options {
buildAST = true; // uses CommonAST by default
ASTLabelType = "antlr.CommonAST";
}
expr
: mexpr (PLUS^ mexpr)* SEMI!
;
mexpr
: atom (STAR^ atom)*
;
atom: INT
;
class transform_l extends Lexer;
WS : (' '
| '\t'
| '\n'
| '\r')
{ $skip; }
;
LPAREN: '('
;
RPAREN: ')'
;
STAR: '*'
;
PLUS: '+'
;
SEMI: ';'
;
protected
DIGIT
: '0'..'9'
;
INT : (DIGIT)+
;
class transform_w extends TreeParser;
options {
buildAST = true;
ASTLabelType = "antlr.CommonAST";
}
expr:! #(PLUS left:expr right:expr)
{
if #right.getType()==INT and int(#right.getText()) == 0:
#expr = #left
elif #left.getType()==INT and int(#left.getText()) ==0:
#expr = #right;
else:
#expr = #(PLUS, left, right);
}
| #(STAR expr expr)
| i:INT
;
|
