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Re: What attributes of a programming language simplify its use?

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On Thursday, December 8, 2022 at 12:45:04 PM UTC-8, Hans-Peter Diettrich wrote:

(snip)

> So let me repeat my questions:

> - Why is "int int" a syntax error? "At least one..." allows for more
> than one type-specifier in declaration-specifiers (6.7).

> - What's "long int long"? My current (Arduino) C++ compiler doesn't flag
> it as an error.

> DoDi
> [This is getting close to comp.lang.c but I'm OK with a little more
> discussion of the design decisions in C's very messy declarations. -John]

Now we can get closer to compilers.

I suspect that it isn't a syntax error, though it will depend on how the
compiler is written.

The compiler (parser) can accept any combination of the specifiers,
and even more than one of them, and then later the compiler decides
that the ones give are not valid.

There was a story many years ago, about a compiler with only one error
message: "SYNTAX ERROR". (Likely in the days of upper case only.)

In any case, it is often easier to write the parser more general than
the actual language, and then flag them later.

But also, the same can be done for the language standard.

As well as I know it, in early C variables default to int. Later, it
was required that they be declared, but the default type was still
int. You could declare:

auto i;

which declares i as automatic, and (by default) int.

It gets more interesting in Fortran, where you can give variables
attributes in separate statements:

      INTEGER I
      DIMENSION I(10,10)
      PUBLIC I
      ALLOCATABLE I
      ASYNCHRONOUS I
      CONTIGUOUS I
      INTENT(IN) I
      OPTIONAL I
      POINTER I
      PROTECTED I
      SAVE I
      TARGET I
      VOLATILE I

All might be legal syntax separately, but not legal in all combinations.

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What attributes of a programming language simplify its use? gah4 <gah4@u.washington.edu> - 2022-12-01 14:20 -0800
  Re: What attributes of a programming language simplify its use? gah4 <gah4@u.washington.edu> - 2022-12-02 02:09 -0800
  Re: What attributes of a programming language simplify its use? Thomas Koenig <tkoenig@netcologne.de> - 2022-12-03 10:25 +0000
    Re: What attributes of a programming language simplify its use? Hans-Peter Diettrich <DrDiettrich1@netscape.net> - 2022-12-03 22:16 +0100
      Re: What attributes of a programming language simplify its use? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2022-12-06 09:56 -0800
        Re: What attributes of a programming language simplify its use? gah4 <gah4@u.washington.edu> - 2022-12-06 12:43 -0800
          Re: What attributes of a programming language simplify its use? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2022-12-07 10:14 +0000
        Re: What attributes of a programming language simplify its use? Hans-Peter Diettrich <DrDiettrich1@netscape.net> - 2022-12-07 12:13 +0100
          Re: What attributes of a programming language simplify its use? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2022-12-07 17:53 -0800
            Re: What attributes of a programming language simplify its use? Hans-Peter Diettrich <DrDiettrich1@netscape.net> - 2022-12-08 21:42 +0100
              Re: What attributes of a programming language simplify its use? gah4 <gah4@u.washington.edu> - 2022-12-08 14:44 -0800
                Re: C types, was What attributes of a programming language simplify its use? Hans-Peter Diettrich <DrDiettrich1@netscape.net> - 2022-12-09 15:01 +0100
              Re: C types, was What attributes of a programming language simplify its use? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2022-12-08 18:35 -0800
              Re: C types, was What attributes of a programming language simplify its use? David Brown <david.brown@hesbynett.no> - 2022-12-09 13:21 +0100
        Re: What attributes of a programming language simplify its use? gah4 <gah4@u.washington.edu> - 2022-12-12 00:00 -0800
      Re: C types, was What attributes of a programming language simplify its use? "marb...@yahoo.co.uk" <marblypup@yahoo.co.uk> - 2022-12-09 07:40 -0800
        Re: C types, was What attributes of a programming language simplify its use? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2022-12-11 10:45 +0000
        Simple to implement and to use Christopher F Clark <christopher.f.clark@compiler-resources.com> - 2022-12-11 19:41 +0200
  Re: What attributes of a programming language simplify its use? Christopher F Clark <christopher.f.clark@compiler-resources.com> - 2022-12-03 23:33 +0000
    Re: What attributes of a programming language simplify its use? gah4 <gah4@u.washington.edu> - 2022-12-03 17:15 -0800

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