{-# LANGUAGE CPP #-}
#if !defined(TESTING) && __GLASGOW_HASKELL__ >= 703
{-# LANGUAGE Safe #-}
#endif
-----------------------------------------------------------------------------
-- |
-- Module      :  Data.Set
-- Copyright   :  (c) Daan Leijen 2002
-- License     :  BSD-style
-- Maintainer  :  libraries@haskell.org
-- Stability   :  provisional
-- Portability :  portable
--
-- An efficient implementation of sets.
--
-- These modules are intended to be imported qualified, to avoid name
-- clashes with Prelude functions, e.g.
--
-- >  import Data.Set (Set)
-- >  import qualified Data.Set as Set
--
-- The implementation of 'Set' is based on /size balanced/ binary trees (or
-- trees of /bounded balance/) as described by:
--
--    * Stephen Adams, \"/Efficient sets: a balancing act/\",
--      Journal of Functional Programming 3(4):553-562, October 1993,
--      <http://www.swiss.ai.mit.edu/~adams/BB/>.
--
--    * J. Nievergelt and E.M. Reingold,
--      \"/Binary search trees of bounded balance/\",
--      SIAM journal of computing 2(1), March 1973.
--
-- Note that the implementation is /left-biased/ -- the elements of a
-- first argument are always preferred to the second, for example in
-- 'union' or 'insert'.  Of course, left-biasing can only be observed
-- when equality is an equivalence relation instead of structural
-- equality.
-----------------------------------------------------------------------------

module Data.Set (
            -- * Strictness properties
            -- $strictness

            -- * Set type
#if !defined(TESTING)
              Set          -- instance Eq,Ord,Show,Read,Data,Typeable
#else
              Set(..)
#endif

            -- * Operators
            , (\\)

            -- * Query
            , S.null
            , size
            , member
            , notMember
            , lookupLT
            , lookupGT
            , lookupLE
            , lookupGE
            , isSubsetOf
            , isProperSubsetOf

            -- * Construction
            , empty
            , singleton
            , insert
            , delete

            -- * Combine
            , union
            , unions
            , difference
            , intersection

            -- * Filter
            , S.filter
            , partition
            , split
            , splitMember
            , splitRoot

            -- * Indexed
            , lookupIndex
            , findIndex
            , elemAt
            , deleteAt

            -- * Map
            , S.map
            , mapMonotonic

            -- * Folds
            , S.foldr
            , S.foldl
            -- ** Strict folds
            , foldr'
            , foldl'
            -- ** Legacy folds
            , fold

            -- * Min\/Max
            , findMin
            , findMax
            , deleteMin
            , deleteMax
            , deleteFindMin
            , deleteFindMax
            , maxView
            , minView

            -- * Conversion

            -- ** List
            , elems
            , toList
            , fromList

            -- ** Ordered list
            , toAscList
            , toDescList
            , fromAscList
            , fromDistinctAscList

            -- * Debugging
            , showTree
            , showTreeWith
            , valid

#if defined(TESTING)
            -- Internals (for testing)
            , bin
            , balanced
            , link
            , merge
#endif
            ) where

import Data.Set.Base as S

-- $strictness
--
-- This module satisfies the following strictness property:
--
-- * Key arguments are evaluated to WHNF
--
-- Here are some examples that illustrate the property:
--
-- > delete undefined s  ==  undefined