From: surrender_it@... (gabriele renzi @ google)
Date: 2004-09-20T19:39:42+09:00
Subject: Ruby 1.9 needs bison?

Hi gurus and nubys,
I just spotted this in the changelog:
	* parse.y: make ruby parser reentrant. merge ripper parser to the
	  real one.  this change makes ruby require bison.

first, thank you for merging ripper.
Alternative interpreter/editor/tool writers out there should realy
appreciate this, I think :)

But there are two things that I don't understand:
First, what are the implications of having a reentrant parser ? 
I mean, this was the only thing that was non reentrant, so this cange
applies to ruby as a whole or was this just a change to make ripper
happy?

Second, what does it meen that now ruby requires bison? I used to
think that bison could generate standalone parsers, do we now need
bison to build ruby, to use ruby, or does it meen that we're simply
forgetting other yacc-like parser generators and focus on just using
bison ?

thank you in advance.