Re: namespace and global function

From	"Alf P. Steinbach" <alf.p.steinbach+usenet@gmail.com>
Newsgroups	comp.lang.c++
Subject	Re: namespace and global function
Date	2011-11-18 13:17 +0100
Organization	A noiseless patient Spider
Message-ID	<ja5idf$9rl$1@dont-email.me> (permalink)
References	<1997973f-a426-4f32-9a58-6195c424f1d3@hh9g2000vbb.googlegroups.com>

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On 17.11.2011 23:09, Jayden Shui wrote:
>
> I have a global function to clone an object.
>
> template<class T>
> T* Clone(T const&  t)
> {
>      return new T(t);
> }

This will use the statically known type, so if T is polymorphic it may 
not necessarily clone in the conventional meaning of the word as 
creating a copy.

Rather, when the dynamic type of `t` is a subclass of T, you'll get a slice.

That's why 'clone' is usually a virtual member function.

Cheers & hth.,

- Alf

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namespace and global function Jayden Shui <jayden.shui@gmail.com> - 2011-11-17 14:09 -0800
  Re: namespace and global function Joshua Maurice <joshuamaurice@gmail.com> - 2011-11-17 15:29 -0800
  Re: namespace and global function SG <s.gesemann@gmail.com> - 2011-11-18 01:00 -0800
  Re: namespace and global function "Alf P. Steinbach" <alf.p.steinbach+usenet@gmail.com> - 2011-11-18 13:17 +0100

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