SOLVED: how to call an inherited, template class constructor from
initializer list of an inheriting, non-template class constructor
l.s.rockfan@web.de wrote:
Salt_Peter wrote:
On Nov 14, 3:30 pm, "l.s.rock...@web.de" <l.s.rock...@web.de> wrote:
Hello,
how do i have to call an inherited, templated class constructor from the
initializer list of the inheriting, non-templated class constructor?
example code:
template<typename T>
class A
{
protected:
sometype* something;
T something_else; /*gives the template some sense here*/
public:
A(sometype* param) : something(param) {};
}
class B : public A<int>
{
public:
B(sometype* param) : A(param) {}; // <== Compiler Error
/* further member functions */
}
The compiler always tries to identify A as a member variable not being
found, instead of the base class' constructor.
The following is a class:
class A { };
this is not:
class A { }
The following declares a class and defines a constructor:
class A
{
A() { }
};
or
// A.hpp (missing include guards)
class A
{
A(); // declaration only
};
// A.cpp
A::A() { } // definition
Basically, a semicolon denotes a declaration.
That's not the point. I just forgot the semicolons in the example.
I found out, that my problem is not only specific to explicit
constructor calls, but occurs everytime I want to call a polymorph
member function of the base class (which is a template class).
I get an undefined reference error from ld.
That's why I start a new post for the more general problem description.
Okay, the problem was that I have used neither the import nor the export
model for template source code organization[1].
I chose the import model and moved the definitions of the template class
member funtions into the header file and everything is working now.
[1] http://www.ddj.com/cpp/184401563
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