isEqualityComparable

1 static assert(isOrderingComparable!int);
2 static assert(isOrderingComparable!string);
3 static assert(!isOrderingComparable!creal);
4 
5 static struct Foo {}
6 static assert(!isOrderingComparable!Foo);
7 
8 static struct Bar
9 {
10     int a;
11     auto opCmp(Bar b1) const { return a - b1.a; }
12 }
13 
14 Bar b1 = Bar(5);
15 Bar b2 = Bar(7);
16 assert(isOrderingComparable!Bar && b2 > b1);