Re: Use of copy constructor in pass by value

From: Risto Lankinen (rlankine_at_hotmail.com)
Date: 02/05/04 

Date: Thu, 05 Feb 2004 13:08:20 GMT

"Rolf Magnus" <ramagnus@t-online.de> wrote in message
news:bvt7vu$9o6$00$1@news.t-online.com...
> madhukar_bm wrote:
>
> > We know that copy constructor is used if a class object is passed by
> > value to a function, is there any logic behind the use of copy
> > constructor as assignment operator could also have been used instead
> > of copy constructor
>
> What would it assign to? You have to create a new object that is a copy
> of an existing one, and that's exactly what the copy constructor is
> for. The assignment operator is for making an existing object a copy of
> another one.

This is in fact an interesting question. If copy constructor is
inaccessible, is the system allowed to default-construct, and
then assign, to simulate the effect of copy construction when
it implicitly needs to? If not, would it make sense to allow it
to happen?

 - Risto -

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