Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > comp.compilers > #2447

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 2020-02-09 02:46 +0100
Organization Compilers Central
Message-ID <20-02-009@comp.compilers> (permalink)
References <20-02-004@comp.compilers> <20-02-005@comp.compilers> <20-02-007@comp.compilers> <20-02-008@comp.compilers>

Show all headers | View raw


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

Back to comp.compilers | Previous | NextPrevious in thread | Next in thread | Find similar


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

csiph-web