The following code example is taken from the book
C++ Templates - The Complete Guide
by David Vandevoorde and Nicolai M. Josuttis, Addison-Wesley, 2002
© Copyright David Vandevoorde and Nicolai M. Josuttis 2002
#include <iostream>
#include <typeinfo>
void foo()
{
std::cout << "foo() called" << std::endl;
}
typedef void FooT(); // FooT is a function type,
// the same type as that of function foo()
int main()
{
foo(); // direct call
// print types of foo and FooT
std::cout << "Types of foo: " << typeid(foo).name()
<< '\n';
std::cout << "Types of FooT: " << typeid(FooT).name()
<< '\n';
FooT* pf = foo; // implicit conversion (decay)
pf(); // indirect call through pointer
(*pf)(); // equivalent to pf()
// print type of pf
std::cout << "Types of pf: " << typeid(pf).name()
<< '\n';
FooT& rf = foo; // no implicit conversion
rf(); // indirect call through reference
// print type of rf
std::cout << "Types of rf: " << typeid(rf).name()
<< '\n';
}