Re: Template<void>

From:
"kanze" <kanze@gabi-soft.fr>
Newsgroups:
comp.lang.c++.moderated
Date:
24 Apr 2006 15:55:42 -0400
Message-ID:
<1145864248.817791.168360@t31g2000cwb.googlegroups.com>
Allan W wrote:

In another thread, someone asked about code like this:

[begin]
class callbackbase {
public:
    virtual void operator()() const { };
    virtual ~callbackbase() = 0;
};
callbackbase::~callbackbase() { }

template < class T >
class callback : public callbackbase {
public:
    typedef void (T::*Func)();
    callback( T& t, Func func ) : object(&t), f(func) { }
    void operator()() const { (object->*f)(); }
private:
    T* object;
    Func f;
};
[end]

The name "callbackbase" is used for the base class,
just to factor out the non-template parts.


Not at all. The class calbackbase defines an interface ; it is
the type which is passed to whatever executes the callback.

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James Kanze GABI Software
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