sbool intRangesOverlapNempty(IntRange a, IntRange b) {
  ret nempty(intersectIntRanges(a, b));
}

sbool intRangesOverlapNempty(int a1, int a2, int b1, int b2) {
  ret intRangesOverlapNempty(intRange(a1, a2), intRange(b1, b2));
}