What is the difference between static_cast and Implicit_cast?

Question

What is implicit_cast? when should I prefer implicit_cast rather than static_cast?

Answer 1

implicit_cast transforms one type to another, and can be extended by writing implicit cast functions, to cast from one type to another.

e.g.

int i = 100;
long l = i;

and

int i = 100;
long l = implicit_cast(i);

are exactly the same code

however you can provide your own implicit casts for your own types, by overloading implicit_cast like the following

template 
inline T implicit_cast (typename mpl::identity::type x) 
{
    return x;
}

See here boost/implicit_cast.hpp for more

Hope this helps

EDIT

This page also talks about implicit_cast New C++

Also, the primary function of static_cast is to perform an non changing or semantic transformation from one type to another. The type changes but the values remain identical e.g.

void *voidPtr = . . .
int* intPtr = static_cast(voidPtr);

I want to look at this void pointer, as if it was an int pointer, the pointer doesn't change, and under the covers voidPtr has exactly the same value as intPtr. An implicit_cast, the type changes but the values after the transformation can be differnet too.