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functors with reference parameters


Disclaimer: VS.NET 2003 (haven't checked any other compiler).

I'm writing functors for my classes.
Because the objects in my containers are large, I'm making my functors take const T& parameters.

If I try std::bind2nd() with one of these classes, I get an error about a reference to a reference.

What's the proper way to declare functors taking const T& parameters so that they play nicely with adapters?

Would it be something like the following? What should I use as the params to unary_function? I can't quite
figure it out from Josuttis.

class myClass
{
// internals redacted
};

class myFunctor : public std::unary_func tion<myClass, void>
{
public:
void operator()(cons t myClass& elem)
{
// do something with elem here
}
};
TIA

Jul 19 '05 #1
0 1733

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