«

Where is the rule that explains why this will not compile? I've always
expected this to work, but it would appear that I haven't run into
this problem yet.

To resolve the problem, do I really need to override every single
method from the Base with the same name as the specific method I am
interested in overriding? I have a good 20 of them in production code.

A simple test case to reproduce what I am experiencing in more
complicated code:


class Base
{
public:
virtual void Foo()
{
}

void Foo(int x)
{

}
};

class Derived : public Base
{
public:
void Foo()
{
}
};

int main()
{

Derived * blah = new Derived();
blah->Foo(5);
delete blah;

return 0;
}

On Apr 7, 10:12*am, Christopher <cp...@austin.rr.com> wrote:
> Where is the rule that explains why this will not compile? I've always
> expected this to work, but it would appear that I haven't run into
> this problem yet.
>
> To resolve the problem, do I really need to override every single
> method from the Base with the same name as the specific method I am
> interested in overriding? I have a good 20 of them in production code.

No. Use "using" (see below).
>
> class Base
> {
> public:
> * *virtual void Foo()
> * *{
> * *}
>
> * *void Foo(int x)
> * *{
>
> * *}
>
> };
>
> class Derived : public Base
> {
> public:
> * *void Foo()
> * *{
> * *}

using Base::Foo(int);
>
> };
>
> int main()
> {
>
> * *Derived * blah = new Derived();
> * *blah->Foo(5);
> * *delete blah;
>
> * *return 0;
> }

On Apr 7, 12:29*pm, Leigh Johnston <le...@i42.co.uk> wrote:
> On 07/04/2011 18:26, red floyd wrote:
>
>
>
>
>
> > On Apr 7, 10:12 am, Christopher<cp...@austin.rr.com> *wrote:
> >> Where is the rule that explains why this will not compile? I've always
> >> expected this to work, but it would appear that I haven't run into
> >> this problem yet.
>
> >> To resolve the problem, do I really need to override every single
> >> method from the Base with the same name as the specific method I am
> >> interested in overriding? I have a good 20 of them in production code.
>
> > No. *Use "using" (see below).
>
> >> class Base
> >> {
> >> public:
> >> * * virtual void Foo()
> >> * * {
> >> * * }
>
> >> * * void Foo(int x)
> >> * * {
>
> >> * * }
>
> >> };
>
> >> class Derived : public Base
> >> {
> >> public:
> >> * * void Foo()
> >> * * {
> >> * * }
>
> > * * * using Base::Foo(int);
>
> That is ill-formed code; instead use:
>
> * * * * using Base::Foo;
>
> /Leigh- Hide quoted text -
>
> - Show quoted text -


I don't really have the option of changing the anything where it is
called. That would be thousands of places in code that had already
been written before I cam aboard and I am sure the bosses would frown
on altering working stuff.

I am thinking of renaming the method I want to override to FooHelper.

I do wonder what the rule is though?..., so I can quote it in my
comments.

On Apr 7, 12:59*pm, Christopher <cp...@austin.rr.com> wrote:
> On Apr 7, 12:29*pm, Leigh Johnston <le...@i42.co.uk> wrote:
>
>
>
>
>
> > On 07/04/2011 18:26, red floyd wrote:
>
> > > On Apr 7, 10:12 am, Christopher<cp...@austin.rr.com> *wrote:
> > >> Where is the rule that explains why this will not compile? I've always
> > >> expected this to work, but it would appear that I haven't run into
> > >> this problem yet.
>
> > >> To resolve the problem, do I really need to override every single
> > >> method from the Base with the same name as the specific method I am
> > >> interested in overriding? I have a good 20 of them in production code.
>
> > > No. *Use "using" (see below).
>
> > >> class Base
> > >> {
> > >> public:
> > >> * * virtual void Foo()
> > >> * * {
> > >> * * }
>
> > >> * * void Foo(int x)
> > >> * * {
>
> > >> * * }
>
> > >> };
>
> > >> class Derived : public Base
> > >> {
> > >> public:
> > >> * * void Foo()
> > >> * * {
> > >> * * }
>
> > > * * * using Base::Foo(int);
>
> > That is ill-formed code; instead use:
>
> > * * * * using Base::Foo;
>
> > /Leigh- Hide quoted text -
>
> > - Show quoted text -
>
> I don't really have the option of changing the anything where it is
> called. That would be thousands of places in code that had already
> been written before I cam aboard and I am sure the bosses would frown
> on altering working stuff.
>
> I am thinking of renaming the method I want to override to FooHelper.
>
> I do wonder what the rule is though?..., so I can quote it in my
> comments.- Hide quoted text -
>
> - Show quoted text -

Hmm, I might have misunderstood. Where are you putting the using
statement?

On Apr 7, 1:02*pm, Leigh Johnston <le...@i42.co.uk> wrote:
> On 07/04/2011 18:59, Christopher wrote:
>
>
>
>
>
> > On Apr 7, 12:29 pm, Leigh Johnston<le...@i42.co.uk> *wrote:
> >> On 07/04/2011 18:26, red floyd wrote:
>
> >>> On Apr 7, 10:12 am, Christopher<cp...@austin.rr.com> * *wrote:
> >>>> Where is the rule that explains why this will not compile? I've always
> >>>> expected this to work, but it would appear that I haven't run into
> >>>> this problem yet.
>
> >>>> To resolve the problem, do I really need to override every single
> >>>> method from the Base with the same name as the specific method I am
> >>>> interested in overriding? I have a good 20 of them in production code.
>
> >>> No. *Use "using" (see below).
>
> >>>> class Base
> >>>> {
> >>>> public:
> >>>> * * *virtual void Foo()
> >>>> * * *{
> >>>> * * *}
>
> >>>> * * *void Foo(int x)
> >>>> * * *{
>
> >>>> * * *}
>
> >>>> };
>
> >>>> class Derived : public Base
> >>>> {
> >>>> public:
> >>>> * * *void Foo()
> >>>> * * *{
> >>>> * * *}
>
> >>> * * * *using Base::Foo(int);
>
> >> That is ill-formed code; instead use:
>
> >> * * * * *using Base::Foo;
>
> >> /Leigh- Hide quoted text -
>
> >> - Show quoted text -
>
> > I don't really have the option of changing the anything where it is
> > called. That would be thousands of places in code that had already
> > been written before I cam aboard and I am sure the bosses would frown
> > on altering working stuff.
>
> > I am thinking of renaming the method I want to override to FooHelper.
>
> > I do wonder what the rule is though?..., so I can quote it in my
> > comments.
>
> You put the using declaration inside the derived class not where it is
> called; read replies more carefully.
>
> /Leigh- Hide quoted text -
>
> - Show quoted text -



Ok This works, but can you explain what that using directive is doing?
If I read the docs on the using directive, I'd expect these to be
equivalent:

class Derived : public Base
{
public:

using Base::Foo;
void Foo()
{
}
};

class Derived : public Base
{
public:

void Base::Foo() // This makes no sense and the compiler tells me
so
{
}
};

On Apr 7, 10:29*am, Leigh Johnston <le...@i42.co.uk> wrote:
> On 07/04/2011 18:26, red floyd wrote:
>
>
>
>
>
>
>
>
>
> > On Apr 7, 10:12 am, Christopher<cp...@austin.rr.com> *wrote:
> >> Where is the rule that explains why this will not compile? I've always
> >> expected this to work, but it would appear that I haven't run into
> >> this problem yet.
>
> >> To resolve the problem, do I really need to override every single
> >> method from the Base with the same name as the specific method I am
> >> interested in overriding? I have a good 20 of them in production code.
>
> > No. *Use "using" (see below).
>
> >> class Base
> >> {
> >> public:
> >> * * virtual void Foo()
> >> * * {
> >> * * }
>
> >> * * void Foo(int x)
> >> * * {
>
> >> * * }
>
> >> };
>
> >> class Derived : public Base
> >> {
> >> public:
> >> * * void Foo()
> >> * * {
> >> * * }
>
> > * * * using Base::Foo(int);
>
> That is ill-formed code; instead use:
>
> * * * * using Base::Foo;

Oops. Brain fart. Thanks.