TITLE: Built in types as classes


PROBLEM: kim@IASTATE.EDU (Jungsun Kim)

I had a debate with my friend over the eligibility of built-in  data types
like integer, double, and etc. to become a class. What I meant is that can
we consider the built-in types as classes in C++?


RESPONSE: steve@taumet.com (Steve Clamage), 30 Mar 93

The built-in types are not full-fledged classes, in the sense that you
cannot derive from them.  Since classes are types, the built-in types
have things in common with classes.

You can use a built-in type as a "class" argument for a template:

	template <class T> class X { ... };
	X<int> x; // "int" used as a "class"

Officially, built-in types have constructors and destructors which
may be invoked, although not all current compilers support the notion.

	int j(3);	// invokes copy constructor int::int(const int&)
	int k;		// invokes default constructor int::int(void)
	j.int::~int();	// "destroy" j

The constructors and destructors have little to do, and while a compiler
might internally treat such code in the same way as for user-defined
classes, it is more likely that these will be treated as special cases.