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GHC 10.0.0.20260917 · lts/ghc-10.0.x · 8fef28d · 2026-11-02

newtypenewtype UniqMap k a

Maps indexed by Uniquable keys

Constructors

Instances8Functor, Eq, Data, Semigroup, Monoid, NFData, …
valueaddToUniqMap_L
  1. :: Uniquable k
  2. => k -> a -> a -> a
  3. -> k
  4. -> a
  5. -> UniqMap k a
  6. -> (Maybe a, UniqMap k a)

Add an element, returns previous lookup result and new map. If old element doesn't exist, add the passed element directly, otherwise compute the element to add using the passed function.