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From: "Hyman Rosen" <hyman.rosen@gmail.com>
Newsgroups: comp.lang.ada
Subject: Re: generics in Ada 83
Date: 14 Sep 2005 08:23:01 -0700
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Date: 2005-09-14T08:23:01-07:00
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Jean-Pierre Rosen wrote:
> In Ada, there is no need to check legality on the expansion of the
> generic. Correct me if I'm wrong, but my understanding of templates is
> that the legality is rechecked for each instantiation.

Well, in Ada, instantiations check the parameters for validity
against whatever contract the generic specifies for them. In C++,
the contract is implied by the usage within the template, so yes,
the legality is rechecked that way. But remember that in C++
template instatntiation is done strictly at compile-time. As far
as the programmer is concerned, either an instantiation validly
meets the template's requirements for its parameters, or the code
fails to compile, and that is true for both languages (or at least
I think that's true for Ada).