concat method
override
Combines two Ord instances into a new one.
Implementation
@override
/// Combines two Ord instances into a new one.
Ord<A> concat(Ord<A> first, Ord<A> second) {
return fromCompare((A a, A b) {
final ox = first.compare(a, b);
return ox != 0 ? ox : second.compare(a, b);
});
}