[ $ "abcdefgh" ] is s  ( --> $ )
  [ 2 ]            is n  ( --> n )
  [ 3 ]            is m  ( --> n )
  [ char d ]       is ch ( --> c )
  [ $ "cd" ]       is ss ( --> $ )

  s n split nip m split drop echo$ cr
  s n split nip echo$ cr
  s -1 split drop echo$ cr
  ch s tuck find split nip m split drop echo$ cr
  ss s tuck find$ split nip m split drop echo$ cr