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From: "Hyman Rosen" <hyman.rosen@gmail.com>
Newsgroups: comp.lang.ada
Subject: Re: Ada generics
Date: 22 Dec 2006 10:26:21 -0800
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Markus E Leypold wrote:
> I think the purpose is not "catching errors" but more likely delivering abstraction.

True enough. Right now, that has to be handled in C++ by documentation.
But the effect is just to let some things work that otherwise would be
stopped.

> Which just goes to show how evil that approach is.

Nonsense. C++'s approach to identifying instantiations serves it
excellently well in a variety of ways - traits classes,
metaprogramming, optimized specializations, and best of all, automatic
instantiation of function templates. You are simply displaying the
usual comp.lang.ada parochialism of "if Ada doesn't have it then you
don't need it". A non-type template parameter can be a reference to a
floating point object, by the way, so the lack isn't all that serious:
    extern double sin(double);
    extern double const epsilon = 1e-6;
    template <double (&F)(double), const double &E>
    double integrate(double from, double to) { ... }
    int main() { integrate<sin, epsilon>(0.0, 3.14); }