Re: Template conversion and default copy constructor

From:
James Kanze <kanze.james@neuf.fr>
Newsgroups:
comp.lang.c++.moderated
Date:
22 Jul 2006 15:31:23 -0400
Message-ID:
<e9t4pd$n5s$1@nntp.aioe.org>
Earl Purple wrote:

Stephan Tolksdorf wrote:

All the compilers I tested produced from the following code executables
that printed "2". Shouldn't the implicitly defined copy constructor be
called?

--
#include <iostream>

class Test{
public:
     Test() : data(0) {}
     template <typename T> Test(T& test) : data(2) { }
     int data;
};

int main(int argc, char* argv[]) {
     Test t1;
     t1.data = 3;
     Test t2(t1);
     std::cout << t2.data;
}
--


No, the default copy-constructor is a closer match (being an exact
match) than the templated one and is called instead.


I think you mistyped here. Didn't you mean the reverse? (The basic way
the sentence is formulated suggests to me that you actually did
understand what was going on, and just inversed the two terms when
typing.)

--
James Kanze kanze.james@neuf.fr
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