Re: Supporting multiple input syntaxes

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From	luser droog <mijoryx@yahoo.com.dmarc.email>
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Subject	Re: Supporting multiple input syntaxes
Date	Sat, 15 Aug 2020 15:20:06 -0700 (PDT)
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On Saturday, August 15, 2020 at 9:46:47 AM UTC-5, David Lovemore wrote:
> It may be useful to consider what you would like to happen if you encounter a
> syntax that is ambiguous or works differently or is for another expected
> syntax from what you are parsing: produce a warning, error or handle quietly,
> or fall over, or don’t care.

Very good points. The parser is backtracking, returning a list of
results. That could conceivably be useful for dealing with ambiguity by
looking at more than just the first result.

Warnings and error messages are going to be trickier I fear. The parser
is built around the idea of Monadic combinators. So my research suggests
that I'll need Monad Transformers to add the state needed for good
messages. There are a bunch of lectures I've found about using these
in Haskell, but not much about how to build them from scratch.

As it is, any error in parsing will just produce no results.

I started a prototype where the input list of characters was instead
a list of (character, line-number, line-position). But it got really
confusing at the time so I stopped. And the few times I've tried to
look at it, I can't figure out what I was thinking.

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Thread

Supporting multiple input syntaxes luser droog <mijoryx@yahoo.com.dmarc.email> - 2020-08-12 15:20 -0700
  Re: Supporting multiple input syntaxes Kaz Kylheku <793-849-0957@kylheku.com> - 2020-08-13 00:43 +0000
  Re: Supporting multiple input syntaxes Hans-Peter Diettrich <DrDiettrich1@netscape.net> - 2020-08-13 10:27 +0200
    Re: Supporting multiple input syntaxes luser droog <mijoryx@yahoo.com.dmarc.email> - 2020-08-13 21:36 -0700
    Re: Supporting multiple input syntaxes luser droog <mijoryx@yahoo.com.dmarc.email> - 2020-08-23 22:16 -0700
  Re: Supporting multiple input syntaxes minforth@arcor.de - 2020-08-13 14:15 -0700
    Re: Supporting multiple input syntaxes luser droog <mijoryx@yahoo.com.dmarc.email> - 2020-08-13 21:37 -0700
    RE: Supporting mulitple input syntaxes Christopher F Clark <christopher.f.clark@compiler-resources.com> - 2020-08-14 12:44 +0300
  Supporting multiple input syntaxes David Lovemore <davidlovemore@gmail.com> - 2020-08-15 06:42 -0700
    Re: Supporting multiple input syntaxes luser droog <mijoryx@yahoo.com.dmarc.email> - 2020-08-15 15:20 -0700
      Re: Supporting multiple input syntaxes David Lovemore <davidlovemore@gmail.com> - 2020-08-16 02:21 -0700
        Re: Supporting multiple input syntaxes luser droog <mijoryx@yahoo.com.dmarc.email> - 2020-08-20 14:45 -0700
          Re: Supporting multiple input syntaxes luser droog <mijoryx@yahoo.com.dmarc.email> - 2020-08-23 19:35 -0700
            Re: implementation languages, was Supporting multiple input syntaxes luser droog <mijoryx@yahoo.com.dmarc.email> - 2020-08-23 20:39 -0700
              Re: implementation languages, was Supporting multiple input syntaxes Thomas Koenig <tkoenig@netcologne.de> - 2020-08-24 17:01 +0000
                Re: implementation languages, was Supporting multiple input syntaxes luser droog <mijoryx@yahoo.com.dmarc.email> - 2020-08-28 10:56 -0700
              Re: stack languages, was Supporting multiple input syntaxes luser droog <mijoryx@yahoo.com.dmarc.email> - 2020-08-24 12:14 -0700
  Re: Supporting multiple input syntaxes gah4 <gah4@u.washington.edu> - 2020-08-23 14:26 -0700
  Re: Supporting multiple input syntaxes antispam@math.uni.wroc.pl - 2021-02-11 23:27 +0000
    Re: Supporting multiple input syntaxes Elijah Stone <elronnd@elronnd.net> - 2021-02-17 01:44 -0800
      Re: Supporting multiple input syntaxes antispam@math.uni.wroc.pl - 2021-02-23 23:28 +0000
        Re: Supporting multiple input syntaxes "ltc...@gmail.com" <ltcmelo@gmail.com> - 2021-03-14 21:08 -0400
  Re: Supporting multiple input syntaxes Rock Brentwood <rockbrentwood@gmail.com> - 2021-03-14 17:36 -0700

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