Re: (Forward) declarations of enums
Francis Glassborow ha scritto:
Lance Diduck wrote:
3) should be able to have a user defined ctors, just like any other
user defined type
I strongly disagree. There is no need for that and would make
enumerations a more complex entity than they are meant to be.
I can already overload operators for them, and C++TPL give examples of
a operator++ for enums. I routinely overload operator<<(std::ostream
&,Enum) form mine for the obvious reasons.
I dont understand how giving enums ctors complicates anything. It
would be very similar to the semantics of union ctors and dtors.
Sorry but I can see very little (if any) use for ctors for (strong)
enums. The only feature I would like to add to enums is the possibility
of a user defined operator=.
You can easily emulate that (and constructors too), by wrapping the enum
inside a struct, for example:
struct E
{
enum EDetail : int
{
/* enumerators */
};
// constructors
constexpr E() : e(default-value-here) {}
explicit constexpr E(int x) : e(x) {}
// conversion operators
explicit constexpr operator int() { return e; }
// other stuff
E& operator=(whatever);
private:
EDetail e;
};
HTH,
Ganesh
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