[antlr-interest] tool for left recursion removal

[Terence Parr]

On Oct 31, 2005, at 5:16 AM, Eric Mahurin wrote:

> On 10/31/05, Terence Parr <parrt at cs.usfca.edu> wrote:
>
> On Oct 30, 2005, at 6:58 AM, Eric Mahurin wrote:
>
> > Before I continue too far off topic (and give another plug for
> > my own LL parser), I'll ask again: anybody know of any software
> > for doing left-recursion removal?
>
> Hi.  New version of http://www.antlr.org/works/index.html does left
> recursion removal :)
>
> Ter
>
> Thanks Terrance!  I just downloaded this and it worked great!   
> Istarted with some yacc grammar, stripped out all the surrounding  
> code, read it into antlrworks, asked it to remove all left  
> recursion, and it looks like it did the right thing!  I'm not sure  
> about actions, but what it did to the grammar looks right.
>
> Would you consider having this left recursion removal as a stand- 
> alone command-line tool?  What you have now is a great start at  
> converting LR grammar (yacc file) to LL grammar.  How about trying  
> to do full conversion?
>
> - removing left recursion
> - left factoring
> - use precedence info to generate expression rules for each level

That is exactly what I hope to build (and integrate into  
antlrworks). :)  Jean's left-factoring is one of the steps...

Ter