public function ascii($subject) : bool
    {
        if ($subject === null) {
            return false;
        }
        $v = '' . $subject;
        return $v === '' ? true : !!preg_match('/^[[:ascii:]]+$/', $v);
    }
public function ascii($subject) : bool
    {
        if ($subject === null) {
            return false;
        }
        $v = '' . $subject;
        return $v === '' ? true : !!preg_match('/^[[:ascii:]]+$/', $v);
    }
public function ascii ( $ subject ) : bool { if ( $ subject === null ) { return false ; } $ v = '' . $ subject ; return $ v === '' ? true : ! ! preg_match ( '/^[[:ascii:]]+$/' , $ v ) ; }
Full ASCII; 0-127.

NB: Returns true on empty ('') string.

@see Validate::string()

@param mixed $subject
Checked stringified.

@return bool
True on empty.
Full ASCII ; 0 - 127 .