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Date: Fri, 3 Apr 2020 16:45:40 -0700 (PDT)
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Subject: Re: Proposal: Auto-allocation of Indefinite Objects
From: Stephen Leake <stephen_leake@stephe-leake.org>
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Xref: reader01.eternal-september.org comp.lang.ada:58305
Date: 2020-04-03T16:45:40-07:00
List-Id: <comp.lang.ada>

On Friday, April 3, 2020 at 3:48:43 PM UTC-7, Stephen Davies wrote:
> Firstly, apologies if this has already been discussed or,
> more likely, if it's a really stupid idea for some reason
> that I haven't thought of.
> 
> My proposal is that it should (sometimes?) be possible to declare
> objects of indefinite types such as String and have the compiler
> automatically declare the space for them without the programmer
> having to resort to access types.

declare
   Foo : String := ...;
begin
   ...
end;

Foo is allocated on the stack; size is taken from the initialization expression.

with Ada.Strings.Unbounded; use Ada.Strings.Unbounded;

declare
   Foo : Unbounded_String; -- empty
begin
   Foo := To_Unbounded ("hi"); -- allocated on the heap
   Foo := Foo & To_Unbounded ("bye"); -- allocation grows
end;
-- deallocated.

-- Stephe