/**
 * @template T of bool
 * @param T $as_number
 * @return (T is true ? __benevolent<float|positive-int> : array{positive-int, int<0, 999999999>})
 */
function hrtime(bool $as_number = false): array|int|float {}

dumpType(hrtime()); // array{int<1, max>, int<0, 999999999>}|false
dumpType(hrtime(true)); // float|int<1, max>|false

/**
 * @template T of bool
 * @param T $as_number
 * @return (T is true ? __benevolent<float|positive-int> : (T is false ? array{positive-int, int<0, 999999999>} : false))
 */
function hrtime(bool $as_number = false): array|int|float|false {}

// before: array{int, int}|float|int
// after:  array{int<1, max>, int<0, 999999999>}|float|int<1, max>|false
dumpType(hrtime(1));