Re: How to make templated operator= more specific?

From:
enjoy.cows@gmail.com
Newsgroups:
comp.lang.c++.moderated
Date:
Mon, 16 Feb 2009 09:08:20 CST
Message-ID:
<f6c29937-e0bc-4c10-b9c9-b1fba44eaf24@w35g2000yqm.googlegroups.com>
On 16 ???, 03:09, enjoy.c...@gmail.com wrote:

Greetings.

it'll be wonderful if somebody could help me.

I have next code:

// templated class Bar is kind of BarBase.

class Foo {
public:
    template<typename T>
        Foo(T f) { bb = new Bar<T>(f); }

    template<typename T> operator Bar<T>() {
        return static_cast<Bar<T>&>(*bb);
    }

private:
    BarBase *bb;

};

I have BarBase and family of inherited Bar<type> classes. When some
Bar<type> converts to BarBase (in constructor of Foo) it needs to be
converted then back to Bar<type> (via conversion operator in Foo).
Certainly, BarBase's pointer can be converted to any of it inherited
classes, including Bar<type> (which is right) and Bar<other_type>. The
latter i'd like to exclude. That means i want compile error when Foo
used like this:

Foo<int> fi;
Bar<int> bi = fi; // Ok.
Bar<double> bd = fi; // Compile error.

How can i implement it?


{ clc++m banner removed -mod }

I'm sorry, that the topic of this message is not about question i've
asked.

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