src/TypeTrait/DateTimeTypeTrait.php
private function isUnixTimestamp($value): bool
    {
        return
            (string)(float)$value == (string)$value &&
            ((float)$value <= PHP_INT_MAX) &&
            ((float)$value >= ~PHP_INT_MAX)
            ;
    }
private function isUnixTimestamp($value): bool
    {
        return
            (string)(float)$value == (string)$value &&
            ((float)$value <= PHP_INT_MAX) &&
            ((float)$value >= ~PHP_INT_MAX)
            ;
    }
private function isUnixTimestamp ( $ value ) : bool { return ( string ) ( float ) $ value == ( string ) $ value && ( ( float ) $ value <= PHP_INT_MAX ) && ( ( float ) $ value >= ~ PHP_INT_MAX ) ; }
Checks whether a value is a valid UNIX timestamp

@param $value
@return bool
Checks whether a value is a valid UNIX timestamp