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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.ada
Subject: Re: Latest suggestion for 202x
Date: Sat, 22 Jun 2019 10:39:24 -0700
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Date: 2019-06-22T10:39:24-07:00
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"Randy Brukardt" <randy@rrsoftware.com> writes:
> "Keith Thompson" <kst-u@mib.org> wrote in message 
> news:lnd0j6kdsl.fsf@kst-u.example.com...
> ...
>> In my example, if A is an array variable and I've written
>>    A(I) = 42;
>> I *can't* replace A by a function without modifying the code that uses
>> it.  Array indexing can appear on the LHS of an assignment; a function
>> call cannot (or at least could not until recently).
>
> That's not strictly true, as anyone who's tried to write an Ada compiler 
> knows. Even in Ada 83, you had to resolve assignments that are overloaded on 
> both sides (the ACATS insists on it):
>
>     Func(I).all := Func2(J);
>
> or
>
>     Func(I).C := Func3(K);
>
> You're right, of course, that you can't put a function there without a 
> dereference (explicit or implicit). And that's still true, we've just hidden 
> the dereference even better.

I should have said that an array indexing operation cannot appear *as*
the LHS of an assignment.  Of course either an array indexing operation
or a function call can be *part of* the LHS of an assignment.

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Will write code for food.
void Void(void) { Void(); } /* The recursive call of the void */