$func? Box?     e.Exp = ;
$func? Channel? e.Exp = ;
$func? Char?    e.Exp = ;
$func? Digit?   e.Exp = ;
$func? Func?    e.Exp = ;
$func? Int?     e.Exp = ;
$func? Letter?  e.Exp = ;
$func? String?  e.Exp = ;
$func? Table?   e.Exp = ;
$func? Vector?  e.Exp = ;
$func? Word?    e.Exp = ;