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From: Robert A Duff <bobduff@shell01.TheWorld.com>
Newsgroups: comp.lang.ada
Subject: Re: Quantified expressions: no support for restriction predicates
Date: Sun, 29 Apr 2012 15:35:18 -0400
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Date: 2012-04-29T15:35:18-04:00
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phil.clayton@lineone.net writes:

> Is that actually possible for a Dynamic_Predicate?  Section 3.2.4 Subtype Predicates, para 27/3 says:
>
>   The discrete_subtype_definition of a loop_parameter_specification
>   shall not denote ... or any subtype to which Dynamic_Predicate
>   specifications apply.

Yeah, I think you're right.  The idea is that we didn't want hidden
inefficiencies.

    type T is new Integer with
        Dynamic_Predicate => T mod 10_000 = 0;
    for X in T loop -- Illegal!

If that were legal, it would probably be grossly inefficient.

- Bob