Contents

module Roman (numerals) where

numerals :: Int -> Maybe String
numerals = Just . go numeralMap
  where
    go pairs@((value, digits):pairs') n
      | n >= value = digits ++ go pairs (n - value)
      | otherwise  = go pairs' n
    go [] _ = ""
    numeralMap = [ (1000, "M"), (900, "CM")
                 , (500, "D"), (400, "CD")
                 , (100, "C"), (90, "XC")
                 , (50, "L"), (40, "XL")
                 , (10, "X"), (9, "IX")
                 , (5, "V"), (4, "IV")
                 , (1, "I") ]

Version data entries

396 entries across 396 versions & 1 rubygems

Version	Path
trackler-2.2.1.180	tracks/haskell/exercises/roman-numerals/examples/success-standard/src/Roman.hs
trackler-2.2.1.179	tracks/haskell/exercises/roman-numerals/examples/success-standard/src/Roman.hs
trackler-2.2.1.178	tracks/haskell/exercises/roman-numerals/examples/success-standard/src/Roman.hs
trackler-2.2.1.177	tracks/haskell/exercises/roman-numerals/examples/success-standard/src/Roman.hs
trackler-2.2.1.176	tracks/haskell/exercises/roman-numerals/examples/success-standard/src/Roman.hs
trackler-2.2.1.175	tracks/haskell/exercises/roman-numerals/examples/success-standard/src/Roman.hs
trackler-2.2.1.174	tracks/haskell/exercises/roman-numerals/examples/success-standard/src/Roman.hs
trackler-2.2.1.173	tracks/haskell/exercises/roman-numerals/examples/success-standard/src/Roman.hs
trackler-2.2.1.172	tracks/haskell/exercises/roman-numerals/examples/success-standard/src/Roman.hs
trackler-2.2.1.171	tracks/haskell/exercises/roman-numerals/examples/success-standard/src/Roman.hs
trackler-2.2.1.170	tracks/haskell/exercises/roman-numerals/examples/success-standard/src/Roman.hs
trackler-2.2.1.169	tracks/haskell/exercises/roman-numerals/examples/success-standard/src/Roman.hs
trackler-2.2.1.167	tracks/haskell/exercises/roman-numerals/examples/success-standard/src/Roman.hs
trackler-2.2.1.166	tracks/haskell/exercises/roman-numerals/examples/success-standard/src/Roman.hs
trackler-2.2.1.165	tracks/haskell/exercises/roman-numerals/examples/success-standard/src/Roman.hs
trackler-2.2.1.164	tracks/haskell/exercises/roman-numerals/examples/success-standard/src/Roman.hs
trackler-2.2.1.163	tracks/haskell/exercises/roman-numerals/examples/success-standard/src/Roman.hs
trackler-2.2.1.162	tracks/haskell/exercises/roman-numerals/examples/success-standard/src/Roman.hs
trackler-2.2.1.161	tracks/haskell/exercises/roman-numerals/examples/success-standard/src/Roman.hs
trackler-2.2.1.160	tracks/haskell/exercises/roman-numerals/examples/success-standard/src/Roman.hs