Data.HashCons

Documentation

data HashCons a

HashCons with a precomputed hash and an IORef to the value.

WARNING: Do not use this type to wrap types whose Eq or Ord instances allow distinguishable values to compare as equal; this will result in nondeterminism or even visible mutation of semantically-immutable values at runtime.

Instances

(Read a, Hashable a) => Read (HashCons a)

Read instance that parses HashCons from the format "hashCons x"

Defined in Data.HashCons.Internal

Methods

readsPrec :: Int -> ReadS (HashCons a)

readList :: ReadS [HashCons a]

readPrec :: ReadPrec (HashCons a)

readListPrec :: ReadPrec [HashCons a]

Show a => Show (HashCons a)

Show instance that displays HashCons in the format "hashCons x"

Defined in Data.HashCons.Internal

Methods

showsPrec :: Int -> HashCons a -> ShowS

show :: HashCons a -> String

showList :: [HashCons a] -> ShowS

Eq a => Eq (HashCons a)

Defined in Data.HashCons.Internal

Methods

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

(/=) :: HashCons a -> HashCons a -> Bool

Ord a => Ord (HashCons a)

NOTE: This instance orders by hash first, and only secondarily by the Ord instance of a, to improve performance.

Defined in Data.HashCons.Internal

Methods

compare :: HashCons a -> HashCons a -> Ordering

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

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

(>) :: HashCons a -> HashCons a -> Bool

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

max :: HashCons a -> HashCons a -> HashCons a

min :: HashCons a -> HashCons a -> HashCons a

Eq a => Hashable (HashCons a)

Defined in Data.HashCons.Internal

Methods

hashWithSalt :: Int -> HashCons a -> Int

hash :: HashCons a -> Int

pattern HashCons :: Hashable a => a -> HashCons a

hashCons :: Hashable a => a -> HashCons a

Create a new HashCons.

unHashCons :: HashCons a -> a

Extract the value from a HashCons.