How can I enable explicit casting from, lets say int, to a user defined class Foo?
I made a conversion constructor from int to Foo, but is that it? I could overload a cast operator from Foo to int, but that is not what I'm looking for.
Is there a way to enable this piece of code?
int i = 5; Foo foo = (Foo)i; Something like this:
struct Foo { explicit Foo(int x) : s(x) { } int s; }; int main() { int i = 5; Foo foo =(Foo)i; } 
explicit ctor.Read about converting constructor.
If you won't set constructor as explicit, it allows you to convert type (which constuctor accepts) to a (newly constructed) class instance.
Here is the example
#include <iostream> template<typename T> class Foo { private: T m_t; public: Foo(T t) : m_t(t) {} }; int main() { int i = 0; Foo<int> intFoo = i; double d = 0.0; Foo<double> doubleFoo = d; } You need a constructor which accecpts an int
class Foo { public: Foo (int pInt) { .... } Foo (double pDouble) { .... } int i = 5; Foo foo(i); // explicit constructors Foo foo2(27); Foo foo3(2.9); Foo foo4 = i; // implicit constructors Foo foo5 = 27; Foo foo6 = 2.1; 
Foo* to Foo ? Dont think so
fooisn't a type, whileFoois a type