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From: Robert A Duff <bobduff@shell01.TheWorld.com>
Newsgroups: comp.lang.ada
Subject: Re: Constructor for a class with a task defined
Date: Sat, 03 Sep 2011 18:11:13 -0400
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Date: 2011-09-03T18:11:13-04:00
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"Rego, P." <pvrego@gmail.com> writes:

>    function Construct return access Small_Class is
>       B : access Small_Class := new Small_Class;
>    begin
>       return B;
>    end Construct;
>
> and got the message "cannot convert local pointer to non-local access type"

The type of B is declared inside Construct, whereas the return type
is declared outside, so it thinks you might be creating a dangling
pointer.  Hence the error.

I suggest you avoid anonymous access types.  They are confusing.
And the rules change in Ada 2012.

> so why does the (type Small_Class_Acc is access all Small_Class;) code 
>
>    function Construct return access Small_Class is
>       B : Small_Class_Acc := new Small_Class;
>    begin
>       return B;
>    end Construct;
>
> works? Should not it get me the same msg?

No, because now B has a global pointer type.

I suggest:

   function Construct return Small_Class_Acc is
      B : Small_Class_Acc := new Small_Class;
   begin
      return B;
   end Construct;

That way, you know where Small_Class_Acc is declared
(probably at library level).

- Bob