[antlr-interest] Tree walk exception
Terence Parr
parrt at cs.usfca.edu
Sat Nov 25 10:01:20 PST 2006
On Nov 25, 2006, at 4:50 AM, Eugene Seliverstov wrote:
> Hello!
>
> Sometimes during work of tree grammar parser NullPointerException
> is thrown.
> Exception happens at
> "org.antlr.runtime.tree.CommonTreeNodeStream.walkBackToMostRecentNodeW
> ithUnvisitedChildren(CommonTreeNodeStream.java :483)"
That line number does not make sense in my 3.0b5 version. that line is:
public boolean hasUniqueNavigationNodes() {
can you check the line number again?
Ter
> and caused by accessing null element at top of stack indexStack.
> This can appear unexpectedly on different rules, on different input
> texts. I think sometimes it's because small lookahead or
> disambiguation of grammar rules, but why it's no detected at code
> generation time?..
>
> Of course, I can provide grammars if it can help (they are too
> large to post here).
> Version of antlr - 3.0b5.
>
> Thank you for regards!
> --
> Best regards,
> Eugene Seliverstov
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