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Re: FIRST_k, FOLLOW_k, k>1

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From Hans-Peter Diettrich <DrDiettrich1@netscape.net>
Newsgroups comp.compilers
Subject Re: FIRST_k, FOLLOW_k, k>1
Date Sun, 9 Feb 2020 02:46:22 +0100
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Am 08.02.2020 um 20:54 schrieb Andy:
> W dniu sobota, 8 lutego 2020 15:36:39 UTC+1 użytkownik Hans-Peter
Diettrich
> napisał:
>> 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}.
>
> Suppose that A is non-starting nonterminal.
> FIRST_k(A) is set of token strings lengths 1..k derived from A or derived
from
> start symbol and begins at A begin?

What's the purpose of exploding the FIRST and FOLLOW sets of a LL(1)
grammar into something more complicated?

IMO you misunderstand the classification of LL grammars and languages :-(

DoDi

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Thread

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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