Yesterday I was stung by some odd behaviour in CommonTokenStream, whereby I
was trying to iterate over the token stream looking for tokens of a specific
type. Since ITokenStream doesn't implement IEnumerable, it appears that the
way to do this is as follows:
for (int i = 0; i < tokenStream.Size(); i++)
{
IToken token = tokenStream.Get(i);
//... do stuff with token...
}
However, I was finding that tokenStream.Size() returned 0, despite my token
stream being non-empty. It seems that the underlying stream is lazily
populated internally, and CommonTokenStream.Size() doesn't trigger a load. I
had to invoke tokenStream.LT(0) to trigger the lazy load prior to looping
through the tokens. Is this intended behaviour? Does is happen in all of the
different runtimes? If so, it's very counterintuitive.
Incidentally, could ITokenStream be updated to implement IEnumerable<IToken>
please? Would others find this useful? I don't mind doing the work, but to
whom should I submit a patch?
Chris
--~--~---------~--~----~------------~-------~--~----~
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
-~----------~----~----~----~------~----~------~--~---
List: http://www.antlr.org/mailman/listinfo/antlr-interest
Unsubscribe:
http://www.antlr.org/mailman/options/antlr-interest/your-email-address
