Re: template function instantiation

From:
"Victor Bazarov" <v.Abazarov@comAcast.net>
Newsgroups:
microsoft.public.vc.language
Date:
Thu, 6 Mar 2008 09:54:40 -0500
Message-ID:
<fqp0jg$4kj$1@news.datemas.de>
George wrote:

For the following code from Bjarne's book, it is stated that template
parameter T for function g will be instantised as int other than
double. My question is why there are not two instantiations for both
int and double version of template function g?

                            ^^^^^^^^^^^^^^^^^^^

Huh?

Are you sure about this? There seems to be no "template parameter T
for function g" because there is no function template function g.
There is the template function 'f', which has a template argument
(parameter, if you like).

Care to restate your question? Do you mean 'function template f'?

[Code]
// section C.13.8.3 Point of Instantiatant Binding

template <class T> void f (T a) { g(a); }

                     ^^^^^^^^^^^^

void g(int);

void h()
{
extern g (double);
f (2);
}
[/Code]

Here is the related statement from Bjarne,

--------------------
Each use of a template for a given set of template arguments defines
a point of instantiation.
That point is the nearest global or namespace scope enclosing its use,
just before the declaration that contains that use.
--------------------

Does it before g (double) is not global function or namespace scope
enclosing its use?


Sorry, I don't understand the question, perhaps some words are
missing there. "Does it <WHAT?> before"?

If yes, I do not know why g (double) is not a
global function, since it is declared as extern and some other
compile unit should expose it?


Please review and maybe repost.

V
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