Greetings!
On Mon, 2010-03-08 at 13:50 +1100, Kieran Simpson wrote:
> I have
>
> ruleA: ruleB;
>
> ruleC: ruleB;
>
> ruleB: ruleD;
>
> In ruleB I want to different target language actions to execute based on
> whether it was ruleA or ruleC that was previously matched. If my
> understanding of syntatic/semantic predicates is correct, they only look
> forwards, not backwards.
>
> Is there a way (without refactoring the grammar) to in rule B know which
> rule it was invoked from (A or C) and make decisions accordingly?
Off the top of my head, pass a parameter.....
ruleA : ruleB[true];
ruleC : ruleB[false];
ruleB [boolean fromA] : ruleD
{ if( fromA )then
....do this stuff....
else
....do that stuff....
};
(the above probably is not precisely the correct meta-syntax, but
hopefully you get the idea...)
-jbb
List: http://www.antlr.org/mailman/listinfo/antlr-interest
Unsubscribe:
http://www.antlr.org/mailman/options/antlr-interest/your-email-address
--
You received this message because you are subscribed to the Google Groups
"il-antlr-interest" group.
To post to this group, send email to [email protected].
To unsubscribe from this group, send email to
[email protected].
For more options, visit this group at
http://groups.google.com/group/il-antlr-interest?hl=en.
