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From: "G.B." <bauhaus@notmyhomepage.invalid>
Newsgroups: comp.lang.ada
Subject: Re: Contracts in generic formal subprogram
Date: Tue, 11 Apr 2023 07:56:45 +0200
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On 08.04.23 10:02, Dmitry A. Kazakov wrote:
> On 2023-04-08 09:00, mockturtle wrote:
> 
>> Should the actual subprogram specify the same contract? I am not sure (and I guess this could be a stumbling block for the adoption of this idea).
> 
> The general principle of substitutability is that the preconditions can be weakened, the postoconditions can be strengthened.

Side track: "weak" and "strong" alone sounding like a valuation to the
uninitiated, but neither technical nor precise; and the "objects" of
comparison of sets of conditions being implicit; and the ARM not
defining a technical term for these adjectives unless weak ordering
helps.

If these adjectives induce confusion, can they be avoided? E.g., by
instead mentioning the sets of Pre- and Post-conditions of those
actual/formal/overriding subprograms. I guess that super- and subset
relations will permit helpfully defining an ordering to be understood
(in general, if not in the ARM).