cryptol/tests/issues/issue187.cry

// Helper synonyms:
// type Char        = [8]
module Enigma where

enigmaLoop : {n}(fin n) => [n]
enigmaLoop = undefined

// Encryption/Decryption
enigma : {n, m} (fin n, fin m) => ([n], [m]) -> [m]
enigma (m, pt) = tail [ True | _ <- rcs ]
  where rcs = [ (m, True)] #
              [ (enigmaLoop, True)
              | _     <- pt
              | (_,_) <- rcs
              ]