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From: Simon Wright <simon@pushface.org>
Newsgroups: comp.lang.ada
Subject: Re: ? Is ok return a  type derived from ada.finalization.controlled
 from a "Pure_Function" ? thanks.
Date: Sat, 26 Jan 2019 11:48:46 +0000
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Date: 2019-01-26T11:48:46+00:00
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danielcheagle@gmail.com writes:

>   Is ok return a type derived from ada.finalization.controlled 
> from a function declared "Pure_Function" ?
>
>   Or yet, is ok declare a fuction returning a 
> controlled type as "pure_function" ?

Given that the documentation of Pure_Function[1] says

   ... the compiler can assume that there are no side effects, and in
   particular that two calls with identical arguments produce the same
   result

and that

   ... there are no static checks to try to ensure that this promise is
   met

it would be a Bad Idea to apply it to your function.

[1] https://gcc.gnu.org/onlinedocs/gnat_rm/Pragma-Pure_005fFunction.html