Function is_num_and_negative

is_num_and_negative(expr): expr is Num & {
__ts_sign: -1;
}
The expression must be a Rat or Flt, otherwise the return value is false. Returns true if expr < 0.
Parameters
- expr: U
  The expression being tested.
Returns expr is Num & {
__ts_sign: -1;
}
- Defined in is_num_and_negative.ts:9