polymorphic use problem

[Angus]

If I have these classes:


class TBase
{
public:
virtual int Execute(Server* srv) = 0;
virtual ~TFunction() {}
};

class Derived : public TBase
{
public:
Derived(const std::string& strA, int ia1)
: m_strA(strA), m_ia1(ia1){
}

virtual int Execute(TServer srv)
{
return SomeFunction(sr v, m_strA, m_ia1);
}
~TRegister() { }
private:
std::string m_strA;
int m_ia1;
};


I want to call the Execute function on a Derived object. How can I
call it?

[Joe Greer]

Re: polymorphic use problem

Angus <anguscomber@gm ail.comwrote in news:67a176cb-5052-45d3-9dc4-
6bc47f3fff1f@27 g2000hsf.google groups.com:

If I have these classes:
>
>
class TBase
{
public:
virtual int Execute(Server* srv) = 0;
virtual ~TFunction() {}
};
>
class Derived : public TBase
{
public:
Derived(const std::string& strA, int ia1)
: m_strA(strA), m_ia1(ia1){
}
>
virtual int Execute(TServer srv)
{
return SomeFunction(sr v, m_strA, m_ia1);
}
~TRegister() { }
private:
std::string m_strA;
int m_ia1;
};
>
>
I want to call the Execute function on a Derived object. How can I
call it?
>

Derived d("blah", 5);

TServer s;
d.Execute(s);

joe

[Joe Greer]

Re: polymorphic use problem

Angus <anguscomber@gm ail.comwrote in news:67a176cb-5052-45d3-9dc4-
6bc47f3fff1f@27 g2000hsf.google groups.com:

If I have these classes:
>
>
class TBase
{
public:
virtual int Execute(Server* srv) = 0;
virtual ~TFunction() {}
};
>
class Derived : public TBase
{
public:
Derived(const std::string& strA, int ia1)
: m_strA(strA), m_ia1(ia1){
}
>
virtual int Execute(TServer srv)
{
return SomeFunction(sr v, m_strA, m_ia1);
}
~TRegister() { }
private:
std::string m_strA;
int m_ia1;
};
>
>
I want to call the Execute function on a Derived object. How can I
call it?
>

I have to point out that as written this won't compile because int
Execute(Server *) isn't implemented any where (unless TServer is a
typedef for a Server *). However, assuming you meant them to be the
same...

If you had:

void f(TBase & t)
{
Server s;
t.Execute(&s);
}
..
..
..

int main()
{
Derived d("blah", 4);

f(d);
}


Is that what you have in mind? Or was it more like:

void f(TBase * t)
{
Server s;
t->Execute(&s);
}

int main()
{
Derived d("blah", 3);
TBase * pT = &d;

f(pT);
}

Either way works. Polymorphism requires a pointer or reference at some
point or you aren't really polymorphic.

joe

[red floyd]

Re: polymorphic use problem

On Jul 10, 9:55 am, Joe Greer <jgr...@doublet ake.comwrote:

Angus <anguscom...@gm ail.comwrote in news:67a176cb-5052-45d3-9dc4-
6bc47f3ff...@27 g2000hsf.google groups.com:
>
>
>

If I have these classes:

>

class TBase
{
public:
    virtual int Execute(Server* srv) = 0;
    virtual ~TFunction() {}
};

>

class Derived : public TBase
{
public:
    Derived(const std::string& strA, int ia1)
    : m_strA(strA), m_ia1(ia1){
    }

>

    virtual int Execute(TServer srv)
    {
        return SomeFunction(sr v, m_strA, m_ia1);
    }
    ~TRegister() { }
private:
    std::string m_strA;
    int m_ia1;
};

>

I want to call the Execute function on a Derived object.  How can I
call it?

>
I have to point out that as written this won't compile because int
Execute(Server *) isn't implemented any where (unless TServer is a
typedef for a Server *).  However, assuming you meant them to be the
same...
>

I also have to point out that these won't compile because the
destructors are improperly named.

[Joe Greer]

Re: polymorphic use problem

red floyd <redfloyd@gmail .comwrote in news:11d9e89e-6410-44ad-9675-
db3db1f230aa@m3 6g2000hse.googl egroups.com:

On Jul 10, 9:55 am, Joe Greer <jgr...@doublet ake.comwrote:

>I have to point out that as written this won't compile because int
>Execute(Serv er *) isn't implemented any where (unless TServer is a
>typedef for a Server *).  However, assuming you meant them to be the
>same...
>>

I also have to point out that these won't compile because the
destructors are improperly named.
>

There is that too. :)

joe