Add Bounded instance

Author: garyb

README.md

@@ -53,6 +53,13 @@ instance ordChar :: Ord Char
 
 Characters can be compared with `compare`, `>`, `>=`, `<` and `<=`.
 
+#### `boundedChar`
+
+``` purescript
+instance boundedChar :: Bounded Char
+```
+
+
 #### `showChar`
 
 ``` purescript
@@ -454,7 +461,4 @@ char :: String -> Char
 
 Converts a string of length `1` to a character.
 
-**Unsafe:** throws runtime exception if length is not `1`.
-
-
-
+**Unsafe:** throws runtime exception if length is not `1`.

src/Data/Char/Char.purs

@@ -1,44 +1,48 @@
 -- | A type and functions for single characters.
 module Data.Char
-  ( Char(),
-    charString,
-    fromCharCode,
-    toCharCode
+  ( Char()
+  , charString
+  , fromCharCode
+  , toCharCode
   ) where
 
-  --| A unicode character.
-  newtype Char = Char String
-
-  -- | Returns the string of length `1` containing only the given character.
-  charString :: Char -> String
-  charString (Char s) = s
-
-  -- | Returns the numeric Unicode value of the character.
-  foreign import toCharCode
-    """
-    function toCharCode(c) {
-      return c.charCodeAt(0);
-    }
-    """ :: Char -> Number
-
-  -- | Constructs a character from the given Unicode numeric value.
-  foreign import fromCharCode
-    """
-    function fromCharCode(c) {
-      return String.fromCharCode(c);
-    }
-    """ :: Number -> Char
-
-  -- | Characters can be compared for equality with `==` and `/=`.
-  instance eqChar :: Eq Char where
-    (==) (Char a) (Char b) = a == b
-
-    (/=) a b = not (a == b)
-
-  -- | Characters can be compared with `compare`, `>`, `>=`, `<` and `<=`.
-  instance ordChar :: Ord Char where
-    compare (Char a) (Char b) = a `compare` b
-
-  -- | Characters can be rendered as a string with `show`.
-  instance showChar :: Show Char where
-    show (Char s) = "Char " ++ show s
+--| A unicode character.
+newtype Char = Char String
+
+-- | Returns the string of length `1` containing only the given character.
+charString :: Char -> String
+charString (Char s) = s
+
+-- | Returns the numeric Unicode value of the character.
+foreign import toCharCode
+  """
+  function toCharCode(c) {
+    return c.charCodeAt(0);
+  }
+  """ :: Char -> Number
+
+-- | Constructs a character from the given Unicode numeric value.
+foreign import fromCharCode
+  """
+  function fromCharCode(c) {
+    return String.fromCharCode(c);
+  }
+  """ :: Number -> Char
+
+-- | Characters can be compared for equality with `==` and `/=`.
+instance eqChar :: Eq Char where
+  (==) (Char a) (Char b) = a == b
+
+  (/=) a b = not (a == b)
+
+-- | Characters can be compared with `compare`, `>`, `>=`, `<` and `<=`.
+instance ordChar :: Ord Char where
+  compare (Char a) (Char b) = a `compare` b
+
+instance boundedChar :: Bounded Char where
+  top = fromCharCode 0
+  bottom = fromCharCode 65535
+
+-- | Characters can be rendered as a string with `show`.
+instance showChar :: Show Char where
+  show (Char s) = "Char " ++ show s