What does =*> mean with regards to context free grammars?

Posted by incrediman on Stack Overflow See other posts from Stack Overflow or by incrediman
Published on 2010-06-13T22:49:18Z Indexed on 2010/06/13 22:52 UTC
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grammar

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context-free-grammar

I've been reading a couple books/online references about compiler theory, and keep seeing that particular operator coming up every once in a while (as seen here), specifically when the current topic is context free grammars. What does it mean? As well, how does it differ from =>?

Explanations with examples distinguishing => from =*> would be most helpful.

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