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Diffstat (limited to 'libraries/base/Data/Ord.hs')
| -rw-r--r-- | libraries/base/Data/Ord.hs | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/libraries/base/Data/Ord.hs b/libraries/base/Data/Ord.hs index 8703c7bdc0..9815259dec 100644 --- a/libraries/base/Data/Ord.hs +++ b/libraries/base/Data/Ord.hs @@ -21,6 +21,7 @@ module Data.Ord ( Ordering(..), Down(..), comparing, + clamp, ) where import Data.Bits (Bits, FiniteBits) @@ -44,6 +45,21 @@ import GHC.Show comparing :: (Ord a) => (b -> a) -> b -> b -> Ordering comparing p x y = compare (p x) (p y) +-- | +-- > clamp (low, high) a = min high (max a low) +-- +-- Function for ensursing the value @a@ is within the inclusive bounds given by +-- @low@ and @high@. If it is, @a@ is returned unchanged. The result +-- is otherwise @low@ if @a <= low@, or @high@ if @high <= a@. +-- +-- >>> clamp (0, 10) 2 +-- 2 +-- +-- >>> clamp ('a', 'm') 'x' +-- 'm' +clamp :: (Ord a) => (a, a) -> a -> a +clamp (low, high) a = min high (max a low) + -- | The 'Down' type allows you to reverse sort order conveniently. A value of type -- @'Down' a@ contains a value of type @a@ (represented as @'Down' a@). -- If @a@ has an @'Ord'@ instance associated with it then comparing two |