Portability	portable
Stability	stable
Maintainer	libraries@haskell.org
Safe Haskell	Trustworthy

Data.Ord

Description

Orderings

Synopsis

Documentation

class Eq a => Ord a whereSource

The Ord class is used for totally ordered datatypes.

Instances of Ord can be derived for any user-defined datatype whose constituent types are in Ord. The declared order of the constructors in the data declaration determines the ordering in derived Ord instances. The Ordering datatype allows a single comparison to determine the precise ordering of two objects.

Minimal complete definition: either compare or <=. Using compare can be more efficient for complex types.

Methods

compare :: a -> a -> Ordering Source

(<) :: a -> a -> Bool Source

(>=) :: a -> a -> Bool Source

(>) :: a -> a -> Bool Source

(<=) :: a -> a -> Bool Source

max :: a -> a -> aSource

min :: a -> a -> aSource

Instances

Ord Bool
Ord Char
Ord Double
Ord Float
Ord Int
Ord Int8
Ord Int16
Ord Int32
Ord Int64
Ord Integer
Ord Ordering
Ord Word
Ord Word8
Ord Word16
Ord Word32
Ord Word64
Ord ()
Ord Arity
Ord Fixity
Ord Associativity
Ord TyCon
Ord TypeRep
Ord ArithException
Ord Fingerprint
Ord IOMode
Ord SeekMode
Ord CUIntMax
Ord CIntMax
Ord CUIntPtr
Ord CIntPtr
Ord CSUSeconds
Ord CUSeconds
Ord CTime
Ord CClock
Ord CSigAtomic
Ord CWchar
Ord CSize
Ord CPtrdiff
Ord CDouble
Ord CFloat
Ord CULLong
Ord CLLong
Ord CULong
Ord CLong
Ord CUInt
Ord CInt
Ord CUShort
Ord CShort
Ord CUChar
Ord CSChar
Ord CChar
Ord GeneralCategory
Ord TypeRepKey
Ord IntPtr
Ord WordPtr
Ord Any
Ord All
Ord NewlineMode
Ord Newline
Ord BufferMode
Ord ExitCode
Ord ArrayException
Ord AsyncException
Ord ThreadStatus
Ord BlockReason
Ord ThreadId
Ord Fd
Ord CRLim
Ord CTcflag
Ord CSpeed
Ord CCc
Ord CUid
Ord CNlink
Ord CGid
Ord CSsize
Ord CPid
Ord COff
Ord CMode
Ord CIno
Ord CDev
Ord Unique
Ord Unique
Ord Version
Ord a => Ord [a]
Integral a => Ord (Ratio a)
Ord (Ptr a)
Ord (FunPtr a)
Ord a => Ord (Maybe a)
Ord (ForeignPtr a)
Ord a => Ord (Last a)
Ord a => Ord (First a)
Ord a => Ord (Product a)
Ord a => Ord (Sum a)
Ord a => Ord (Dual a)
Ord a => Ord (Down a)
Ord (Fixed a)
(Ord a, Ord b) => Ord (Either a b)
(Ord a, Ord b) => Ord (a, b)
(Ix i, Ord e) => Ord (Array i e)
(Ord a, Ord b, Ord c) => Ord (a, b, c)
(Ord a, Ord b, Ord c, Ord d) => Ord (a, b, c, d)
(Ord a, Ord b, Ord c, Ord d, Ord e) => Ord (a, b, c, d, e)
(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f) => Ord (a, b, c, d, e, f)
(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g) => Ord (a, b, c, d, e, f, g)
(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h) => Ord (a, b, c, d, e, f, g, h)
(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h, Ord i) => Ord (a, b, c, d, e, f, g, h, i)
(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h, Ord i, Ord j) => Ord (a, b, c, d, e, f, g, h, i, j)
(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h, Ord i, Ord j, Ord k) => Ord (a, b, c, d, e, f, g, h, i, j, k)
(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h, Ord i, Ord j, Ord k, Ord l) => Ord (a, b, c, d, e, f, g, h, i, j, k, l)
(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h, Ord i, Ord j, Ord k, Ord l, Ord m) => Ord (a, b, c, d, e, f, g, h, i, j, k, l, m)
(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h, Ord i, Ord j, Ord k, Ord l, Ord m, Ord n) => Ord (a, b, c, d, e, f, g, h, i, j, k, l, m, n)
(Ord a, Ord b, Ord c, Ord d, Ord e, Ord f, Ord g, Ord h, Ord i, Ord j, Ord k, Ord l, Ord m, Ord n, Ord o) => Ord (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o)

data Ordering Source

Constructors

LT
EQ
GT

Instances

Bounded Ordering
Enum Ordering
Eq Ordering
Data Ordering
Ord Ordering
Read Ordering
Show Ordering
Ix Ordering
Typeable Ordering
Generic Ordering
Monoid Ordering

comparing :: Ord a => (b -> a) -> b -> b -> Ordering Source

 comparing p x y = compare (p x) (p y)

Useful combinator for use in conjunction with the xxxBy family of functions from Data.List, for example:

   ... sortBy (comparing fst) ...