Re: FIRST_k, FOLLOW_k, k>1

From	Andy <borucki.andrzej@gmail.com>
Newsgroups	comp.compilers
Subject	Re: FIRST_k, FOLLOW_k, k>1
Date	2020-02-08 11:54 -0800
Organization	Compilers Central
Message-ID	<20-02-008@comp.compilers> (permalink)
References	<20-02-004@comp.compilers> <20-02-005@comp.compilers> <20-02-007@comp.compilers>

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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?
for example, if we have E->AB, First_4(A) are also strings from B? (if in
First_4(A) exists shorter strings than 4)
It seems that in both situation Follow_4(A) will complicated and contains all
strings from B,C,D... for E->ABCD (if exists in A,B,C shorter stings)

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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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