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Date: Tue, 12 Nov 2002 08:48:13 -0500
From: Hyman Rosen <hyrosen@mail.com>
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Subject: Re: Charles: Generic_Find
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Date: 2002-11-12T08:48:13-05:00
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Preben Randhol wrote:
> Victor Porton wrote:
>>Why Generic_Find is generic? Why not just pass the predicate
>>as a function access? Doing so would avoid the need of
>>generic instantiation.
> 
> Doesn't sound to me like a good Ada solution to do that. Sounds more
> like C++

Hey! VP is commenting on Charles, which is based on the C++ STL,
whose version of find is a template. The C++ standard library
uses generic instantiation almost everywhere.

Anyway, in C++ the reason to have the predicate be generic is
the many varieties of objects that can stand in for a predicate.
It also introduces potentially significant optimization
opportunities, since for predicates, function call overhead can
easily dwarf the amount of computation done by the predicate
itself.