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From: Andy <borucki.andrzej@gmail.com>
Newsgroups: comp.compilers
Subject: Re: FIRST_k, FOLLOW_k, k>1
Date: Sat, 8 Feb 2020 11:54:11 -0800 (PST)
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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)