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Re: Why are ambiguous grammars usually a bad idea? Why are languages usually defined and implemented with ambiguous grammars?

From gah4 <gah4@u.washington.edu>
Newsgroups comp.compilers
Subject Re: Why are ambiguous grammars usually a bad idea? Why are languages usually defined and implemented with ambiguous grammars?
Date 2021-12-30 13:40 -0800
Organization Compilers Central
Message-ID <21-12-031@comp.compilers> (permalink)
References <21-12-003@comp.compilers> <21-12-017@comp.compilers> <21-12-022@comp.compilers>

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On Wednesday, December 29, 2021 at 7:28:33 PM UTC-8, gah4 wrote:

(snip, I wrote)

> This reminds me of learning associativity of exponentiation (**)
> in Fortran IV (I believe it isn't in the Fortran 66 standard) before I
> learned it in algebra class. I suspect that there are others I learned
> from programming before learning them in math class

(snip)

> [Fortran has always had ** exponentiation, starting with the original
> version in 1956. It always bound tighter than +-*/ but wasn't
> associative, A**B**C not allowed, -John]

It was, at least, in Fortran IV for IBM 360/370:

https://atariwiki.org/wiki/attach/Fortran/IBM_FORTRAN_IV-Language_1973.pdf

My 8th grade graduation present was the above manual, though maybe
one year earlier.   I used to read IBM reference manuals like books,
from start to finish.  By the end of summer, I had run many Fortran programs.

As well as I know it, IBM Fortran IV was the input to the 1966 standard,
but not all features were included.  It might also be that extensions were
added later.
[I used Fortran H on Princeston's 360/91 in a summer job I had in
college in about 1973. -John]

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Re: Why are ambiguous grammars usually a bad idea? Why are languages usually defined and implemented with ambiguous grammars? Kaz Kylheku <480-992-1380@kylheku.com> - 2021-12-29 18:48 +0000
  Re: Why are ambiguous grammars usually a bad idea? Why are languages usually defined and implemented with ambiguous grammars? Jan Ziak <0xe2.0x9a.0x9b@gmail.com> - 2021-12-29 16:05 -0800
    Re: Why are ambiguous grammars usually a bad idea? Why are languages usually defined and implemented with ambiguous grammars? Kaz Kylheku <480-992-1380@kylheku.com> - 2021-12-30 18:00 +0000
      Re: Why are ambiguous grammars usually a bad idea? Why are languages usually defined and implemented with ambiguous grammars? Kaz Kylheku <480-992-1380@kylheku.com> - 2021-12-30 20:08 +0000
  Re: Why are ambiguous grammars usually a bad idea? Why are languages usually defined and implemented with ambiguous grammars? gah4 <gah4@u.washington.edu> - 2021-12-29 18:41 -0800
    Re: Why are ambiguous grammars usually a bad idea? Why are languages usually defined and implemented with ambiguous grammars? Kaz Kylheku <480-992-1380@kylheku.com> - 2021-12-30 18:14 +0000
      Re: Why are ambiguous grammars usually a bad idea? Why are languages usually defined and implemented with ambiguous grammars? Jan Ziak <0xe2.0x9a.0x9b@gmail.com> - 2021-12-30 13:47 -0800
        Re: What does = mean, was Why are ambiguous grammars usually a bad idea? Jan Ziak <0xe2.0x9a.0x9b@gmail.com> - 2021-12-30 17:10 -0800
        Re: Why are ambiguous grammars usually a bad idea? Why are languages usually defined and implemented with ambiguous grammars? mac <acolvin@efunct.com> - 2022-01-03 19:51 +0000
          Re: for or against equality, was Why are ambiguous grammars usually a bad idea? gah4 <gah4@u.washington.edu> - 2022-01-03 21:07 -0800
            Re: for or against equality, was Why are ambiguous grammars usually a bad idea? Thomas Koenig <tkoenig@netcologne.de> - 2022-01-04 19:23 +0000
            Re: for or against equality, was Why are ambiguous grammars usually a bad idea? gah4 <gah4@u.washington.edu> - 2022-01-04 13:26 -0800
    Re: Why are ambiguous grammars usually a bad idea? Why are languages usually defined and implemented with ambiguous grammars? gah4 <gah4@u.washington.edu> - 2021-12-30 13:40 -0800
  Re: why do people choose a language, was Why are ambiguous grammars usually a bad idea? Jan Ziak <0xe2.0x9a.0x9b@gmail.com> - 2021-12-30 20:19 -0800

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