{-# LANGUAGE Safe #-}

-- |
--
-- Module      :  Data.Bool
-- Copyright   :  (c) The University of Glasgow 2001
-- License     :  BSD-style (see the file libraries/base/LICENSE)
--
-- Maintainer  :  libraries@haskell.org
-- Stability   :  stable
-- Portability :  portable
--
-- The 'Bool' type and related functions.
--

module Data.Bool
    (-- *  Booleans
     Bool(..),
     -- **  Operations
     (&&),
     (||),
     not,
     otherwise,
     bool
     ) where

import Prelude (Bool(..), (&&), (||), not, otherwise)

-- $setup
-- >>> import Prelude

-- | Case analysis for the 'Bool' type. @'bool' f t p@ evaluates to @f@
-- when @p@ is 'False', and evaluates to @t@ when @p@ is 'True'.
--
-- This is equivalent to @if p then t else f@; that is, one can
-- think of it as an if-then-else construct with its arguments
-- reordered.
--
-- @since base-4.7.0.0
--
-- ==== __Examples__
--
-- Basic usage:
--
-- >>> bool "foo" "bar" True
-- "bar"
-- >>> bool "foo" "bar" False
-- "foo"
--
-- Confirm that @'bool' f t p@ and @if p then t else f@ are
-- equivalent:
--
-- >>> let p = True; f = "bar"; t = "foo"
-- >>> bool f t p == if p then t else f
-- True
-- >>> let p = False
-- >>> bool f t p == if p then t else f
-- True
--
bool :: a -> a -> Bool -> a
bool :: forall a. a -> a -> Bool -> a
bool a
f a
_ Bool
False = a
f
bool a
_ a
t Bool
True  = a
t