- Similar to Python
- Commutivity
(a + b) is same as (b + a)

therefore,T opAdd(U u);

serves both. - Reverse operators
opDiv: opDiv_r: a / b

- Comparison
opEquals: a == b b == a a != b b != a opCmp: a < b b < a a <= b b <= a a > b b > a a >= b b >= a