Laurence Tratt

> I would think that perhaps a new declaration like %allow-unused Unmatched could be used to disable such an error This feels quite yacc-y to me! I can certainly live...

I must admit, this isn't a feature that I'd thought about. At first glance, it seems an awkward fit with LR parsing, in the sense that, at least conceptually, you...

Sorry @nikomatsakis for not saying thanks for your comment (I'm only nearly a year late)! Coming back to this one with the benefit of hindsight, I think that I'd be...

> I think actually '\' and '"' may be valid lex names that need escaping here. Good point! Yes, this needs checking.

I must admit that I haven't used start states, so it's difficult for me to write "deep" documentation on them. I keep hoping that someone else will chip in with...

Thanks @ratmice ! @FranklinChen does that help -- are there things you would still need to know to use this feature?

@FranklinChen Thanks for reporting back! @ratmice I wonder if that's intentional on our part or not? I don't know the bison syntax for start states well enough to know.

> It does accept leading initial spaces, but that doesn't do what one might think. It copies such lines verbatim into the generated sources. I didn't expect that! Do we...

I'm not a big fan of ignoring such lines, because I guess that some people expect this to interact with lex code? Assuming that's correct, my instinct is to make...

Linux does support this, but the man page you linked uses the term "negative". I didn't remember this detail, but Linux is more forgiving than the BSDs in this regard:...