a = b = 1 just syntactic sugar?
Martin v. Löwis
martin at v.loewis.de
Tue Jun 10 01:13:34 EDT 2003
"Greg Ewing (using news.cis.dfn.de)" <g2h5dqi002 at sneakemail.com> writes:
> It *might* be the case that there is an equivalent LL(1)
> grammar for any grammar that pgen can handle, but I can't
> think of a proof of this off the top of my head.
I think it is as easy as this:
- Replace a construct FOO* with FOO_seq, and define
FOO_seq: /* empty */
| FOO FOO_seq
- Replace a construct [FOO] with FOO_opt, and define
FOO_opt: /* empty */
| FOO
This, of course, requires that the follow-sets of FOO_seq and FOO_opt
are disjoint with the first-sets of FOO, but pgen requires this
property as well.
Regards,
Martin
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