Default parameter acting weird

[dds82]

I have a function that I declared like this in the header file:

CString func(const SomeClass &x, bool y=true);

and the compiler gives me error C2572 ("Redefinition of default parameter&quot on this line in the header file, not the C++ source file. However, when I change the line to

CString func(const SomeClass &x, bool y);

I get errors in other files that say "Error: 'func' does not take 1 parameter(s)".

What's going on?

 

[tchouch]

CString func(const SomeClass &x, bool y=true);
You can use it if Your Function is a class member. Questions:
1.Maybe, You have another Function with such name in this class?
2. Is the class SomeClass defined before this line and known for the header (for example, so:
class SomeClass
3. Maybe, You have class member named y? For example, so:
class SomeClass;
class MySuperClass
{
int x;
int y;
CString func(const SomeClass &x, bool y=true);
...
};
Try to change them.
If it all does not work, easy add to Your class (for example, after int y such function:
inline CString func(const SomeClass &x)
{
return func(x, true);
}

 

[dds82]

This is a global function. It's not part of any class.

Right now, I've already done your last suggestion; it's the only thing I could get to work. But why is it giving trouble with the default parameter?

 

[tchouch]

The problem is only if You write:
int func(bool y = true);

int func(bool y = true)
{
return 2 * y;
}

Use that instead:
int func(bool y = true);

int func(bool y ) //No default value in definition
{
return 2 * y;
}

 

[dds82]

Yes. I knew that. That's not the problem here. I didn't do that.