template<class T>
class A
{
template<class Y>
A(const A<Y> &)
{
// whatever
}
};
void f()
{
A<int> a1;
A<int> a2(a1); // here
}
Will my "templated copy constructor" be invoked?
cheers,
Marcin Kalicinski
5  4244  ka****@poczta.o net.pl wrote: Will my "templated copy constructor" be invoked?
No. A template is never considered to be a copy constructor,
even if its signature might match that of a copy constructor.
You need to provide a separate copy constructor.
--
<mailto:di***** ******@yahoo.co m> <http://www.dietmar-kuehl.de/>
<http://www.contendix.c om> - Software Development & Consulting ka****@poczta.o net.pl wrote: template<class T>
class A
{
template<class Y>
A(const A<Y> &)
{
// whatever
}
};
void f()
{
A<int> a1;
A<int> a2(a1); // here
}
Will my "templated copy constructor" be invoked?
No. Since a1 and a2 are the same type, the non-template copy-c-tor
(generated by the compiler) will be used to create 'a2'.
V
"Victor Bazarov" <v.********@com Acast.net> wrote in message
news:lk******** ***********@new sread1.mlpsca01 .us.to.verio.ne t... ka****@poczta.o net.pl wrote: template<class T>
class A
{
template<class Y>
A(const A<Y> &)
{
// whatever
}
};
void f()
{
A<int> a1;
A<int> a2(a1); // here
}
Will my "templated copy constructor" be invoked?
No. Since a1 and a2 are the same type, the non-template copy-c-tor
(generated by the compiler) will be used to create 'a2'.
V
Hmm, I thought there is no such thing like a "template copy ctor",
regardless of a probably matching signature. But I might be wrong. Could you
shed some light on this dark corner in my knowledge, please?
Cheers
Chris
Chris Theis wrote: "Victor Bazarov" <v.********@com Acast.net> wrote in message
news:lk******** ***********@new sread1.mlpsca01 .us.to.verio.ne t...
ka****@poczta .onet.pl wrote:
template<cla ss T>
class A
{
template<class Y>
A(const A<Y> &)
{
// whatever
}
};
void f()
{
A<int> a1;
A<int> a2(a1); // here
}
Will my "templated copy constructor" be invoked?
No. Since a1 and a2 are the same type, the non-template copy-c-tor
(generated by the compiler) will be used to create 'a2'.
V
Hmm, I thought there is no such thing like a "template copy ctor",
regardless of a probably matching signature. But I might be wrong. Could you
shed some light on this dark corner in my knowledge, please?
You are correct, there is no such thing as "template copy ctor". That's
why that expression was put in double quotes. Why the sarcasm? Do you
not understand the implied sense when things are in quotes? Then I can
explain. When something is put in quotes, it means that the 'as if' or
'like' rule is used. You know, right now I can write that I am answering
your "question". Get it? "Question". Implying that you did not actually
ask one, seemingly intending only to make a sarcastic remark...
V
"Victor Bazarov" <v.********@com Acast.net> wrote in message
news:jO******** **********@news read1.mlpsca01. us.to.verio.net ... Chris Theis wrote: "Victor Bazarov" <v.********@com Acast.net> wrote in message
news:lk******** ***********@new sread1.mlpsca01 .us.to.verio.ne t...
ka****@poczta .onet.pl wrote:
template<cla ss T>
class A
{
template<class Y>
A(const A<Y> &)
{
// whatever
}
};
void f()
{
A<int> a1;
A<int> a2(a1); // here
}
Will my "templated copy constructor" be invoked?
No. Since a1 and a2 are the same type, the non-template copy-c-tor
(generated by the compiler) will be used to create 'a2'.
V
Hmm, I thought there is no such thing like a "template copy ctor",
regardless of a probably matching signature. But I might be wrong. Could
you shed some light on this dark corner in my knowledge, please?
You are correct, there is no such thing as "template copy ctor". That's
why that expression was put in double quotes. Why the sarcasm? Do you
not understand the implied sense when things are in quotes? Then I can
explain. When something is put in quotes, it means that the 'as if' or
'like' rule is used. You know, right now I can write that I am answering
your "question". Get it? "Question". Implying that you did not actually
ask one, seemingly intending only to make a sarcastic remark...
V
Hi Victor,
take a deep breath & relax ;-) There was no sarcasm intended on my side,
because I really wasn´t 100% sure about the templated copy ctor issue.
That´s why I asked - it was really meant as a question. Sorry, if it sounded
sarcastic because it certainly was not intended that way!
Cheers
Chris This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
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