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From: =?utf-8?Q?Yannick_Duch=C3=AAne_=28Hibou57?=
 =?utf-8?Q?=29?=
 <yannick_duchene@yahoo.fr>
Newsgroups: comp.lang.ada
Subject: Re: pragma Pure (Ada)
Date: Sat, 01 Oct 2011 04:11:14 +0200
Organization: Ada @ Home
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Date: 2011-10-01T04:11:14+02:00
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Le Sat, 01 Oct 2011 03:50:36 +0200, Yannick Duch=C3=AAne (Hibou57)  =

<yannick_duchene@yahoo.fr> a =C3=A9crit:

> In =E2=80=9CA Brief Introduction to Ada 2012=E2=80=9D (a great paper f=
rom John Barnes) ->
> http://www2.adacore.com/wp-content/uploads/2006/03/Ada2012_Rational_In=
troducion.pdf

On page 13, there's something I don't feel to understand

> Programmers have always moaned about the need for many
> explicit conversions in Ada. Accordingly, implicit
> conversions from anonymous access types to named access
> types are now permitted provided the explicit conversion is
> legal. The idea is that the need for an explicit conversion
> with access types should only arise if the conversion could
> fail. A curious consequence of this change is that a
> preference rule is needed for the equality of anonymous
> access types.

=E2=80=9Ca preference rule is needed for the equality of anonymous acces=
s types=E2=80=9D ?  =

What does that mean ?


-- =

=E2=80=9CSyntactic sugar causes cancer of the semi-colons.=E2=80=9D  [Ep=
igrams on  =

Programming =E2=80=94 Alan J. =E2=80=94 P. Yale University]
=E2=80=9CStructured Programming supports the law of the excluded muddle.=
=E2=80=9D [Idem]
Java: Write once, Never revisit