Relude.Container.Reexport

This instance was available since 1.4.1.0 only for GHC-9.4+

Note: prior to hashable-1.3.0.0, hash 0.0 /= hash (-0.0)

The hash of NaN is not well defined.

Note: prior to hashable-1.3.0.0, hash 0.0 /= hash (-0.0)

The hash of NaN is not well defined.

Note: Prior to hashable-1.3.0.0 the hash computation included the second argument of Arg which wasn't consistent with its Eq instance.

In general, hash (Compose x) ≠ hash x. However, hashWithSalt satisfies its variant of this equivalence.

Note that, in the presence of hash collisions, equal HashMaps may behave differently, i.e. extensionality may be violated:

>>> data D = A | B deriving (Eq, Show)>>> instance Hashable D where hashWithSalt salt _d = salt

>>> x = fromList [(A,1), (B,2)]>>> y = fromList [(B,2), (A,1)]

>>> x == yTrue>>> toList x[(A,1),(B,2)]>>> toList y[(B,2),(A,1)]

In general, the lack of extensionality can be observed with any function that depends on the key ordering, such as folds and traversals.

The ordering is total and consistent with the Eq instance. However, nothing else about the ordering is specified, and it may change from version to version of either this package or of hashable.

<> = union

If a key occurs in both maps, the mapping from the first will be the mapping in the result.

Examples

>>> fromList [(1,'a'),(2,'b')] <> fromList [(2,'c'),(3,'d')]fromList [(1,'a'),(2,'b'),(3,'d')]

mempty = empty

mappend = union

If a key occurs in both maps, the mapping from the first will be the mapping in the result.

Examples

>>> mappend (fromList [(1,'a'),(2,'b')]) (fromList [(2,'c'),(3,'d')])fromList [(1,'a'),(2,'b'),(3,'d')]

Create singleton HashMap from key-value pair.

>>> one (3, "foo") :: HashMap Int TextfromList [(3,"foo")]

law> Relude.length (one @(HashMap k v) (k, v)) ≡ 1

Note that, in the presence of hash collisions, equal HashSets may behave differently, i.e. extensionality may be violated:

>>> data D = A | B deriving (Eq, Show)>>> instance Hashable D where hashWithSalt salt _d = salt

>>> x = fromList [A, B]>>> y = fromList [B, A]

>>> x == yTrue>>> toList x[A,B]>>> toList y[B,A]

In general, the lack of extensionality can be observed with any function that depends on the key ordering, such as folds and traversals.

<> = union

O(n+m)

To obtain good performance, the smaller set must be presented as the first argument.

Examples

>>> fromList [1,2] <> fromList [2,3]fromList [1,2,3]

mempty = empty

mappend = union

O(n+m)

To obtain good performance, the smaller set must be presented as the first argument.

Examples

>>> mappend (fromList [1,2]) (fromList [2,3])fromList [1,2,3]

Create singleton HashSet.

>>> one 42 :: HashSet IntfromList [42]

law> Relude.length (one @(HashSet a) x) ≡ 1

Folds in order of increasing key.

Traverses in order of increasing key.

Create singleton IntMap from key-value pair.

>>> one (3, "foo") :: IntMap TextfromList [(3,"foo")]

law> Relude.length (one @(IntMap a) x) ≡ 1

Create singleton IntSet.

>>> one 42 :: IntSetfromList [42]

law> size (one x) ≡ 1

Folds in order of increasing key.

Traverses in order of increasing key.

Create singleton Map from key-value pair.

>>> one (3, "foo") :: Map Int TextfromList [(3,"foo")]

law> Relude.length (one @(Map k v) (k, v)) ≡ 1

Create singleton Seq.

>>> one 42 :: Seq IntfromList [42]

law> Relude.length (one @(Seq a) x) ≡ 1

Folds in order of increasing key.

Create singleton Set.

>>> one 42 :: Set IntfromList [42]

law> Relude.length (one @(Set a) x) ≡ 1

For long or infinite lists use fromList because it uses LazyByteString otherwise use fromListN which uses StrictByteString.

Be aware that 'fromList . toList = id' only for unfrozen CallStacks, since toList removes frozenness information.

Performs replacement on invalid scalar values:

>>> :set -XOverloadedLists>>> ['\55555'] :: Text"\65533"

Performs replacement on invalid scalar values:

>>> :set -XOverloadedLists>>> ['\55555'] :: Data.Text.Lazy.Text"\65533"