Error when I compute size of a list about alpinelang HOT 3 CLOSED

type error: type '( $27 or Int )' doesn't match 'Int':
  if numb > 0

func repeat_int (_ numb: Int) -> Int ::
  if numb > 0
    then 1 + repeat_int(numb-1)
    else 0

type error: type 'String' doesn't match 'String':
  if numb > 0

func cond_string(_ numb: Int, _ s: String) -> String ::
  if numb > 0
    then s
    else "No"

func not(_ bool: Bool) -> Bool ::
  if bool = true
    then false
    else true

func not(_ bool: Bool) -> Bool ::
  if bool
    then false
    else true