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From: Janis Papanagnou <janis_papanagnou+ng@hotmail.com>
Newsgroups: comp.lang.c
Subject: Re: Two questions on arrays with size defined by variables
Date: Mon, 10 Feb 2025 03:12:18 +0100
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On 10.02.2025 00:50, Keith Thompson wrote:
> Janis Papanagnou <janis_papanagnou+ng@hotmail.com> writes:
> [...]
>> I had other languages in mind.[*]
>>
>> Janis
>>
>> [*] For example Simula:
>>
>> begin
>>     integer n;
>>     n := inint;
>>     begin
>>         integer array arr (1:n);
>>         arr(5) := 9;
>>     end
>> end
>>
>> (Which is also understandable, since in Simula declarations must appear
>> before statements in any block.)
> 
> Apparently Simula doesn't allow variables to be initialized in their
> declarations. 

The Cim compiler I use actually supports a constant initialization -
but I'm positive this is non-standard! - like

begin
    integer n = 10;
    integer array arr (1:n);
    arr(5) := 9;
end


> Because of that, `n := inint;` (where inint is actually a
> call to a value-returning procedure) is a separate statement.  If
> Simula supported C-style initializers, then presumably the inner block
> would not be needed:

Indeed. (See non-standard example above.)

> 
>     begin
>         integer n := inint;
>         integer array arr (1:n);
>         arr(5) := 9;
>     end
> 

This is not possible because 'n' isn't a constant here (and 'inint' is
a function, as you say). - So you're correct that the block would not
be an inherent necessity for that declaration [with Cim compiler].
A general statement for the standard Simula language cannot be given,
though, since it's undefined.

Janis