[Haskell-cafe] Parser left recursion

[Roman Cheplyaka]

* Kim-Ee Yeoh <ky3 at atamo.com> [2013-02-24 19:22:33+0700]
> On Sun, Feb 24, 2013 at 7:09 PM, Roman Cheplyaka <roma at ro-che.info> wrote:
> 
> > Thus, your
> > recursion is well-founded — you enter the recursion with the input
> > strictly smaller than you had in the beginning.
> >
> 
> Perhaps you meant /productive/ corecursion? Because the definition "A ::= B
> A" you gave is codata.

Or perhaps you meant that the production itself, when interpreted as a
definition, is corecursive? Well, yes, and so is any CFG written in BNF.
But that doesn't buy us much, and is irrelevant to the discussion of
parsing left-recursive grammars.

Roman