[antlr-interest] Troubel With Keywords / Whitespaces

[Jason]

Hello,

I've run into a problem when I run the lexer generated
with the grammar which follows on, for instance, this
input stream:  'select foo bar bar selectbar foo'. 
Everything works ducky except that rather than
matching the 'REG_ID' rule, 'selectbar' matches the
'EAL_SELECT' rule followed by the "REG_ID' rule.  It's
obvious why this is happening but I can't figure out
the best way to fix it.  I know it's unusual to make
each Keyword a rule, but I make heavy use of semantic
predicates to determine whether a keyword has been
matched or not.  The only solution I've come up with
is to change 'select' to 'select ' but there's got to
be something better.  If anyone has any thoughts I'd
greatly appreciate it.

class TestLexer extends Lexer;

options
{
  k = 8;
  exportVocab=Test;
}

EAL_SELECT: "select"   { };

protected ALPHA_CHAR: ('a'..'z' | 'A'..'Z') { };
protected DIGIT: ('0'..'9');

REG_ID: ALPHA_CHAR ( ALPHA_CHAR | DIGIT )* { };

// Whitespace -- ignored
WS	:	
  (	' ' |	'\t' |	'\f' |	(options
{generateAmbigWarnings=false;}
			:	"\r\n" 
			|	'\r'   
			|	'\n'   
			)
			{ newline(); }
		)+
		{ _ttype = Token.SKIP; }
  ;

-jason

-jason

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