[antlr-interest] Paranoia, paranoia...
Sam Barnett-Cormack
s.barnett-cormack at lancaster.ac.uk
Tue Aug 4 06:32:36 PDT 2009
Okay, I might just be being paranoid, but I wanted to sanity check
something...
There's a rule "constraint" that matches LPAREN, a potentially unlimited
number of other things (including nested constraints), then RPAREN. I
wanted a rule that will match any number of these.
Any LPAREN after a constraint will be the start of another constraint.
So the rule I have is:
constraints : constraint ((LPAREN)=>constraint)* -> ^(CONSTRAINTS
constraint+) ;
I believe this will match one or more constraints, and make a new
subtree with each constraint a node under it (potentially being a
subtree themselvs).
Does this do what I think it does?
NB: constraint+ doesn't work because it can't tell how far to look
ahead. It has to finish matching one and then see if there's more.
--
Sam Barnett-Cormack
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