[antlr-interest] Non-determinism clarification.

[Bharath]

Hi all,

I have a lexer rule of the form Time: 

Time: ('T'|"TIME")(Integer);

It clashes with my "Identifier" rule, as expected. So, I did this:

Time: ('T'|"TIME"){$setType(IDENT);}
	(Integer);

but it doesn't work. Is this wrong usage? I cant have the "Time" rule in my
parser because it would make "T" and "TIME" keywords and they are not.

If I try to make "Identifier" rule protected and add a third rule 

IDENT_OR_TIME: (....)$setType(IDENT);(Integer)?{$setType(Time);} it still
doesn't work. (...) contains the general ('a'..'z') etc components that form
an identifier.

Any ideas?

Thanks!

Bharath.

-----Original Message-----
From: Mark Lentczner [mailto:markl at glyphic.com] 
Sent: Tuesday, May 18, 2004 12:07 PM
To: antlr-interest at yahoogroups.com
Subject: Re: [antlr-interest] greedy/non-greedy problem.


On May 18, 2004, at 9:34 AM, jbb at acm.org wrote:

> Bharath :-
>
>> I replaced it with IDENT DOT IDENT DOT (IDENT (DOT IDENT)*)? And it 
>> worked.
> But you do realize that the above rule recognizes a different
> language than your original rule?

He's right!  I misread the original rule...  I thought the trailing 
IDENT was optional, but it isn't....   That's what I get for trying to 
read my e-mail while my toddler is running around!

Jbb's solution is correct.

	- Mark



 
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