description

# Comparator<T> typedef Null safety

int Comparator (

1. T a,
2. T b

)

The signature of a generic comparison function.

A comparison function represents an ordering on a type of objects. A total ordering on a type means that for two values, either they are equal or one is greater than the other (and the latter must then be smaller than the former).

A Comparator function represents such a total ordering by returning

- a negative integer if `a` is smaller than `b`,
- zero if `a` is equal to `b`, and
- a positive integer if `a` is greater than `b`.

## Implementation

    typedef Comparator<T> = int Function(T a, T b);