[antlr-interest] Allowing whitespace in symbols

[soraz30]

I have a problem, and I'm not even sure I'm close to solving it.


I have a grammar, that defines two types of symbols, in seperate
symbol tables
AList
BList


A symbol in one of the lists, must be allowed to include spaces in
their names i.e.

in the DiagnoseList, I have "Foo Bar" as a valid entry.
in the InterventionList, I have "Poo Par" as a valid entry.

In my lexer, I have a rule that basically says (pseudo-code)
ID : [a-z0-9 ]+
   { if text in AList, _ttype=ASYMBOL; 
     if text in BList, _ttype=BSYMBOL;
   }


The parser then has
Line:- ASYMBOL BSYMBOL

On the input "Foo Bar Poo Par", this, ofcourse fails, because the rule
for ASYMBOL (that is: ID), has globbed the Poo Bar as part of the
reg-exp for ID.

Is there any way to achieve this? What I'm looking for, is a way for
the ID rule to say "Ok: That is enough. I now match an entry from one
of the lists.". 

I thought about an approach to match it manually against the lists,
and push the remainder back on the input-stream. Is this a viable
solution? Is it possible?

The symbol tables are loaded from an external source at run-time, so I
cant just insert them as literals (which, by the way, works nicely).

Thanks in advance
Asger



 
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