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Tony · Guest

C++ Gurus,

What does the standard say about the following case ?

bool func1(double d1, double d2=1.0)
{
return d1 < d2;
}

bool func2(bool (*pf)(double d1, double d2=2.0))
{
return pf(1.0);
}

int main()
{
bool (*pf)(double d1, double d2=3.0);

pf = func1;
pf(1.0); //d2 = ? in func1 when func1 is called?
//in MSC++6.0, d2=3.0, is this standard?
func2(pf); //d2 = ? in func1 when func2 calls func1 ?
//in MSC++6.0, d2=2.0, is this standard?

return 0;

/*About declaration of "bool (*pf)(double d1, double d2=3.0);"
pf must have the above form or "bool (*pf)(double, double=3.0);".
If the declaration is "bool (*pf)(double d1, double d2);",
"pf(1.0);" has compiler error, even if func1 has d2=0.0
as default. Is this behaviour standard? */
}

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Daniel Frey · Guest

Tony wrote:

Ben Hutchings · Guest

Tony wrote:

Dhruv · Guest

On Fri, 16 Jan 2004 08:02:42 -0500, Tony wrote:

Tony · Guest

bool func1(double d1, double d2=2.0)
{
return d1 < d2;
}

bool (*pf)(double, double); //this is only the legal form
pf = func1;
pf(1.0, 2.0);
pf(1.0); //this has compiler error in MSC++6.0.
//how to call func1 with d2 as default via pf?
//impossible in the standard ??

Tony

"Dhruv"