Re: Learning only one lexer made me blind to its hidden assumptions

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From	George Neuner <gneuner2@comcast.net>
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Subject	Re: Learning only one lexer made me blind to its hidden assumptions
Date	Thu, 14 Jul 2022 16:46:36 -0400
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On Wed, 13 Jul 2022 19:52:45 -0000 (UTC), antispam@math.uni.wroc.pl
wrote:

>Hmm, from flex manual:
>
>:       -Ce, --ecs
>:              construct equivalence classes
>:
>:       -Cm, --meta-ecs
>:              construct meta-equivalence classes
>
>If you want smaller tables use options above and flex DFA will
>work on character classes.

But note that Flex /may/ run considerably slower if you make heavy use
of equivalence classes.  IIRC, that results in (moral equivalent of)
NFA rather than DFA.

George
[On modern computers it's hard to imagine a scanner so big that the space
savings from those two options are worth it. 64K PDP-11 and all that. -John]

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Learning only one lexer made me blind to its hidden assumptions Roger L Costello <costello@mitre.org> - 2022-07-07 17:49 +0000
  Re: Learning only one lexer made me blind to its hidden assumptions luser droog <luser.droog@gmail.com> - 2022-07-12 19:49 -0700
    Re: Learning only one lexer made me blind to its hidden assumptions Juan Miguel Vilar Torres <jvilar@uji.es> - 2022-07-13 01:46 -0700
  Re: Learning only one lexer made me blind to its hidden assumptions "Ev. Drikos" <drikosev@gmail.com> - 2022-07-13 14:58 +0300
  Re: Learning only one lexer made me blind to its hidden assumptions antispam@math.uni.wroc.pl - 2022-07-13 19:52 +0000
    Re: Learning only one lexer made me blind to its hidden assumptions George Neuner <gneuner2@comcast.net> - 2022-07-14 16:46 -0400
      Re: Learning only one lexer made me blind to its hidden assumptions antispam@math.uni.wroc.pl - 2022-07-15 20:14 +0000
  Re: Learning only one lexer made me blind to its hidden assumptions Kaz Kylheku <480-992-1380@kylheku.com> - 2022-07-15 14:16 +0000

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