X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=GHC%2FBase.lhs;h=f957a6d55cffc743fe8d1285e5d8897e28feb369;hb=69daab60bb6f89433a0394182481d721dc2f42fd;hp=76ade714e2764c65e927b8827f95c57736a7df35;hpb=550bd82e4fa20eb3ac0613d5a8e145bf69e4d9cd;p=ghc-base.git diff --git a/GHC/Base.lhs b/GHC/Base.lhs index 76ade71..f957a6d 100644 --- a/GHC/Base.lhs +++ b/GHC/Base.lhs @@ -279,6 +279,12 @@ The rest of the prelude list functions are in GHC.List. ---------------------------------------------- \begin{code} +-- | 'foldr', applied to a binary operator, a starting value (typically +-- the right-identity of the operator), and a list, reduces the list +-- using the binary operator, from right to left: +-- +-- > foldr f z [x1, x2, ..., xn] == x1 `f` (x2 `f` ... (xn `f` z)...) + foldr :: (a -> b -> b) -> b -> [a] -> b -- foldr _ z [] = z -- foldr f z (x:xs) = f x (foldr f z xs) @@ -344,6 +350,12 @@ augment g xs = g (:) xs ---------------------------------------------- \begin{code} +-- | 'map' @f xs@ is the list obtained by applying @f@ to each element +-- of @xs@, i.e., +-- +-- > map f [x1, x2, ..., xn] == [f x1, f x2, ..., f xn] +-- > map f [x1, x2, ...] == [f x1, f x2, ...] + map :: (a -> b) -> [a] -> [b] map _ [] = [] map f (x:xs) = f x : map f xs @@ -383,6 +395,13 @@ mapFB c f x ys = c (f x) ys -- append ---------------------------------------------- \begin{code} +-- | Append two lists, i.e., +-- +-- > [x1, ..., xm] ++ [y1, ..., yn] == [x1, ..., xm, y1, ..., yn] +-- > [x1, ..., xm] ++ [y1, ...] == [x1, ..., xm, y1, ...] +-- +-- If the first list is not finite, the result is the first list. + (++) :: [a] -> [a] -> [a] (++) [] ys = ys (++) (x:xs) ys = x : xs ++ ys @@ -402,8 +421,9 @@ mapFB c f x ys = c (f x) ys \begin{code} -- |The 'Bool' type is an enumeration. It is defined with 'False' --- first so that the corresponding 'Enum' instance will give @'fromEnum' --- False@ the value zero, and @'fromEnum' True@ the value 1. +-- first so that the corresponding 'Prelude.Enum' instance will give +-- 'Prelude.fromEnum' 'False' the value zero, and +-- 'Prelude.fromEnum' 'True' the value 1. data Bool = False | True deriving (Eq, Ord) -- Read in GHC.Read, Show in GHC.Show @@ -495,11 +515,15 @@ data Ordering = LT | EQ | GT deriving (Eq, Ord) type String = [Char] {-| The character type 'Char' is an enumeration whose values represent -Unicode characters. A character literal in Haskell has type 'Char'. - -To convert a 'Char' to or from an 'Int', use 'Prelude.toEnum' and -'Prelude.fromEnum' from the 'Enum' class respectively (equivalently -'ord' and 'chr' also do the trick). +Unicode (or equivalently ISO 10646) characters. +This set extends the ISO 8859-1 (Latin-1) character set +(the first 256 charachers), which is itself an extension of the ASCII +character set (the first 128 characters). +A character literal in Haskell has type 'Char'. + +To convert a 'Char' to or from the corresponding 'Int' value defined +by Unicode, use 'Prelude.toEnum' and 'Prelude.fromEnum' from the +'Prelude.Enum' class respectively (or equivalently 'ord' and 'chr'). -} data Char = C# Char# @@ -526,6 +550,7 @@ instance Ord Char where "x# `ltChar#` x#" forall x#. x# `ltChar#` x# = False #-} +-- | The 'Prelude.toEnum' method restricted to the type 'Data.Char.Char'. chr :: Int -> Char chr (I# i#) | int2Word# i# `leWord#` int2Word# 0x10FFFF# = C# (chr# i#) | otherwise = error "Prelude.chr: bad argument" @@ -533,6 +558,7 @@ chr (I# i#) | int2Word# i# `leWord#` int2Word# 0x10FFFF# = C# (chr# i#) unsafeChr :: Int -> Char unsafeChr (I# i#) = C# (chr# i#) +-- | The 'Prelude.fromEnum' method restricted to the type 'Data.Char.Char'. ord :: Char -> Int ord (C# c#) = I# (ord# c#) \end{code}