Re: class template function specialization error

From:
"Greg Herlihy" <greghe@pacbell.net>
Newsgroups:
comp.lang.c++.moderated
Date:
9 May 2006 08:23:19 -0400
Message-ID:
<1147123550.360531.24190@y43g2000cwc.googlegroups.com>
seaswar wrote:

I am trying to specialize the default constructor and a static member
function in my template class but get an error (distilled code is
below). I tried prefixing the call to f() in the constructor
initialization with C<int>:: but get same error.
Please help
Thanks
Suresh

x.h:
template<typename T>
class C {
public:
         C();
         static int f();
private:
         int m;
};

x.cpp:
#include "x.h"

template<>
C<int>::C() : m(f()) { }

template<>
int C<int>::f() { return 0; }


The specialized constructor calls (and thereby instantiates) the static
method C<int>::f before the specialization for f appears. The solution
is to specialize f() first:

     template<>
     int C<int>::f() { return 0; }

     template<>
     C<int>::C() : m(f()) { }

These specializations should also be placed in the header file with the
rest of the class template declaration in order to ensure that C<int>
is consistently specialized.

Greg

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