In 3.3.3 Recursive Rules you say:
"...you should always use left recursion, because it can parse a
sequence of any number of elements with bounded stack space. Right
recursion uses up space on the Bison stack in proportion to the number
of elements in the sequence ..."
In ANTLR (an LL(1) parser) I believe that the issue of putting lists in
the wrong order is resolved. I wonder if that is a good thing to
consider for Bison.
As just a comment, rather that go into the details of stack size
wouldn't it be better to point out that in LR(1) grammars, BNF with
LL(1) list definitions cause problems and should not be used. I guess I
'm confused as to the knowledge of the assumed audience for this
document and whether they know about LR(1) and LL(1) grammars. You did
mentions LALR(1) grammars in 1.1 Languages and Context-Free Grammar and
IELR(1) and LR(1), but not SLR(1) (an immediate precursor to LALR(1), so
I assume that the target audience has some knowledge about LR(1) and
LL(1) lists.
I'm not done with the document, but so far I've seen no reference to
EBNF, a.k.a., ambiguous grammars, but I do see their use. I hope this
will be mentioned.
These comments are incidental to my reading of the document. If you like
I can continue in a more methodical way and if you's like, can
contribute alternate wording/text for your review. The current document
is much, much better than the one I looked at in 2013 or thereabout. You
are doing a great job.
thanks
art
