Function compareDefined

src/sort.js:27–35

(compare = ascending)

}

export function compareDefined(compare = ascending) {
  if (compare === ascending) return ascendingDefined;
  if (typeof compare !== "function") throw new TypeError("compare is not a function");
  return (a, b) => {
    const x = compare(a, b);
    if (x || x === 0) return x;
    return (compare(b, b) === 0) - (compare(a, a) === 0);
  };
}

export function ascendingDefined(a, b) {
  return (a == null || !(a >= a)) - (b == null || !(b >= b)) || (a < b ? -1 : a > b ? 1 : 0);