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From: Simon Wright <simon@pushface.org>
Newsgroups: comp.lang.ada
Subject: Re: Incompatible types for array conversion
Date: Wed, 22 Jul 2015 08:13:22 +0100
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Date: 2015-07-22T08:13:22+01:00
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Niklas Holsti <niklas.holsti@tidorum.invalid> writes:

> The conversion is rejected because of the conversion condition in RM
> 4.6 (24.5/2): "The component subtypes shall statically match". The
> component (sub)types are Real and Length, which are different types,
> although Length is derived from Real. If you change the declaration of
> Length to be
>
>    subtype Length is Real;
>
> the conversion becomes legal.

I tried

   generic
      dim:		positive;
      type Real is digits <>;
   package Vectors is
      type Vector is array (1..dim) of Real'Base;

but it still failed. (GPL 2015, FSF 5.1.0)