Re: How can I use structs in a named enum?

[simendsjo]

On Wed, 29 Feb 2012 12:15:35 +0100, simendsjo <simend...@gmail.com> wrote:

.. That is >> enum E : Struct {}

struct S {
     int a;
}

// ok
enum E : S {
     a = S(1),
}

// Error: need member function opCmp() for struct S to compare
/*
enum E2 : S {
     a = S(1),
     b = S(2)
}
*/

struct S2 {
     int a;
     int opCmp(ref const S2 other)
     {
         return a == other.a ? 0 : (a < other.a ? -1 : 1);
     }
}

// Error: function opcmp.S2.opCmp (ref const(S2) other) is not callable using argument types (E3)

// Error: cast(const(S2))S2(1) is not an lvalue

// Error: function opcmp.S2.opCmp (ref const(S2) other) is not callable using argument types (E3)

// Error: cast(const(S2))S2(1) is not an lvalue
enum E3 : S2 {
     a = S2(1),
     b = S2(2)
}

void main() {
}


So E3 is passed as the parameter to S2.opCmp..?

Hmm.. By removing ref const in opCmp, it works as expected