Removing Left Recursion in ANTLR

Posted by prosseek on Stack Overflow See other posts from Stack Overflow or by prosseek
Published on 2010-06-08T17:34:29Z Indexed on 2010/06/08 17:42 UTC
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As is explained in http://stackoverflow.com/questions/2652060/removing-left-recursion , there are two ways to remove the left recursion.

Modify the original grammar to remove the left recursion using some procedure
Write the grammar originally not to have the left recursion

What people normally use for removing (not having) the left recursion with ANTLR? I've used flex/bison for parser, but I need to use ANTLR. The only thing I'm concerned about using ANTLR (or LL parser in genearal) is left recursion removal.

In practical sense, how serious of removing left recursion in ANTLR? Is this a showstopper in using ANTLR? Or, nobody cares about it in ANTLR community?
I like the idea of AST generation of ANTLR. In terms of getting AST quick and easy way, which method (out of the 2 removing left recursion methods) is preferable?

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