pure virtual parameters

[Alex]

I have a doubt. Given a function like this:

class bar {
public:
virtual void foo(int i = 0) = 0;
};

when implementing this virtual function, will the above enforce the default
parameter in all implementations?

class der : public bar
{
void foo(int i) {}
};

or should I again specify "int i = 0"?

Thanks.

[Bo Hunter]

Alex wrote:

I have a doubt. Given a function like this:

class bar {
public:
virtual void foo(int i = 0) = 0;
};

when implementing this virtual function, will the above enforce the
default parameter in all implementations?

class der : public bar
{
void foo(int i) {}
};

or should I again specify "int i = 0"?

Thanks.

I took your code pasted it in to a test project
and calling der.foo() will produce a error on GCC 3.2.
Then added void foo( int i = 0 ) and calling der.foo()
does not produce a error. So I guess that it does not
get the default parameter.
--
Thank You
Bo Hunter
Registered Linux User #393766 http://counter.li.org/

[Andre Kostur]

"Alex" <[e-mail]> wrote in
news:db**********@nsnmpen2-gest.nuria.telefonica-data.net:

I have a doubt. Given a function like this:

class bar {
public:
virtual void foo(int i = 0) = 0;
};

when implementing this virtual function, will the above enforce the
default parameter in all implementations?
Nope. (At least not where foo() is called through a pointer/reference to a
more-derived type....)
class der : public bar
{
void foo(int i) {}
};

or should I again specify "int i = 0"?

You again specify "int i = 0".

[Phlip]

Alex wrote:

I have a doubt. Given a function like this:

class bar {
public:
virtual void foo(int i = 0) = 0;
};

when implementing this virtual function, will the above enforce the default parameter in all implementations?

class der : public bar
{
void foo(int i) {}
};

or should I again specify "int i = 0"?

Specify again (or pick another method to default the parameter).

Default parameters resolve at compile time, so they resolve based on their
object's static type. Virtual methods resolve at runtime.

--
Phlip
http://www.c2.com/cgi/wiki?ZeekLand