Re: how to call an inherited, template class constructor from initializer list of an inheriting, non-template class constructor

From:
"l.s.rockfan@web.de" <l.s.rockfan@web.de>
Newsgroups:
comp.lang.c++
Date:
Sat, 15 Nov 2008 11:05:57 +0100
Message-ID:
<gfm71c$m33$1@bruford.hrz.tu-chemnitz.de>
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.

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