Re: syntax complexity

From	gah4 <gah4@u.washington.edu>
Newsgroups	comp.compilers
Subject	Re: syntax complexity
Date	2023-02-20 09:57 -0800
Organization	Compilers Central
Message-ID	<23-02-053@comp.compilers> (permalink)
References	(1 earlier) <23-02-045@comp.compilers> <23-02-047@comp.compilers> <23-02-050@comp.compilers> <29156_1676600565_63EEE4F4_29156_1009_1_23-02-051@comp.compilers> <23-02-052@comp.compilers>

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On Monday, February 20, 2023 at 9:46:04 AM UTC-8, Roger L Costello wrote:

> Scenario: you have a language that has a BNF. You write a statement in the language.
> It is a relatively simple, basic statement. The statement conforms to the BNF.
> To show its conformance, you write the derivation of the statement.
> Surprisingly, deriving the statement takes many, many rules.
> Does that signify that the language's syntax is too complex?

One suggestion above based it on the size of the standard. That isn't
quite as good as it could be, as some standard writers are wordier
than others, but maybe not so bad.

Another choice is on the size of the BNF.

I don't think I would rate it on one statement, but the whole BNF of
the language. One statement, such as an assignment statement, could
use a lot of rules. Whole language syntax complexity should be on the
whole BNF.

One complication, depending on how you write BNF. Some statements,
such as in PL/I, have items that can be in any order, but you only
have at most one of each. That is complicated to write in BNF, but I
don't believe complicates the syntax, as seen by people.
[There are definitely things that are hard to say in BNF, even though
they're intuitively simple.  Another is floating point numbers with
optional "." and "E" but you need at least one of them. -John]

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syntax complexity gah4 <gah4@u.washington.edu> - 2023-02-15 15:08 -0800
  Re: syntax complexity Thomas Koenig <tkoenig@netcologne.de> - 2023-02-16 06:32 +0000
  Re: syntax complexity Hans-Peter Diettrich <DrDiettrich1@netscape.net> - 2023-02-16 12:03 +0100
    Re: syntax complexity gah4 <gah4@u.washington.edu> - 2023-02-16 11:33 -0800
      Re: syntax complexity gah4 <gah4@u.washington.edu> - 2023-02-16 16:08 -0800
      Re: syntax complexity Roger L Costello <costello@mitre.org> - 2023-02-20 15:09 +0000
        Re: syntax complexity gah4 <gah4@u.washington.edu> - 2023-02-20 09:57 -0800
          Re: syntax complexity anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2023-02-21 08:14 +0000
            Re: syntax complexity anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2023-02-21 18:39 +0000
              Re: ireegular expressions, syntax complexity anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2023-02-22 10:55 +0000
            Re: irregular expressions, syntax complexity arnold@freefriends.org (Aharon Robbins) - 2023-02-22 08:53 +0000
            Re: irregular expressions, syntax complexity Kaz Kylheku <864-117-4973@kylheku.com> - 2023-02-23 00:34 +0000
        Re: syntax complexity George Neuner <gneuner2@comcast.net> - 2023-02-20 13:49 -0500
      syntax complexity Christopher F Clark <christopher.f.clark@compiler-resources.com> - 2023-02-21 20:54 +0200

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