Re: FIRST_k, FOLLOW_k, k>1

From	Hans-Peter Diettrich <DrDiettrich1@netscape.net>
Newsgroups	comp.compilers
Subject	Re: FIRST_k, FOLLOW_k, k>1
Date	2020-02-08 11:00 +0100
Organization	Compilers Central
Message-ID	<20-02-007@comp.compilers> (permalink)
References	<20-02-004@comp.compilers> <20-02-005@comp.compilers>

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Am 06.02.2020 um 23:16 schrieb Andy:
> I search examples,
> E->aWbXYcdZ
> W->w
> X->x
> Y->y
> Z->z
>
> if for FIRST(k=4) wil be: E={awbx} W={wbxy} X={xycd} Y={ycdz} Z={z}
> what is convention?

Your grammar definitely is LL(1). You should provide a grammar that
requires longer lookahead.

IMO the FIRST set covers all *different* sequences, in your case
FIRST(E)={a} hence LL(1).
Only if there exist multiple alternatives starting with 'a' they have to
be listed as e.g. FIRST(E)={ax, ay}.

Dunno about the FOLLOW set, perhaps it can stay LL(1)?

DoDi

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FIRST_k, FOLLOW_k, k>1 Andy <borucki.andrzej@gmail.com> - 2020-02-06 10:43 -0800
  Re: FIRST_k, FOLLOW_k, k>1 Andy <borucki.andrzej@gmail.com> - 2020-02-06 14:16 -0800
    Re: FIRST_k, FOLLOW_k, k>1 Hans-Peter Diettrich <DrDiettrich1@netscape.net> - 2020-02-08 11:00 +0100
      Re: FIRST_k, FOLLOW_k, k>1 Andy <borucki.andrzej@gmail.com> - 2020-02-08 11:54 -0800
        Re: FIRST_k, FOLLOW_k, k>1 Hans-Peter Diettrich <DrDiettrich1@netscape.net> - 2020-02-09 02:46 +0100
  FIRST_k, FOLLOW_k, k&gt;1 Christopher F Clark <christopher.f.clark@compiler-resources.com> - 2020-02-07 16:12 +0200
  Re: FIRST_k, FOLLOW_k, k>1 honey crisis <gaztoast@gmail.com> - 2020-02-08 18:18 -0800

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