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GHC 9.10.3 · lts/ghc-9.10.x · c74966e · 2026-09-27

Modulererebase-1.21.2Haskell2010

Control.Selective.Rigid.Freer

  • 1 type
  • 6 values
valuefoldSelect :: Monoid m => (forall x. f x -> m) -> Select f a -> m
#

Concatenate all effects of a free selective computation.

valuegetEffects :: Functor f => Select f a -> [f ()]
#

Collect all possible effects in the order they appear in a free selective computation.

valuegetNecessaryEffect :: Functor f => Select f a -> Maybe (f ())
#

Extract the necessary effect from a free selective computation. Note: there can be at most one effect that is statically guaranteed to be necessary.

valuegetPure :: Select f a -> Maybe a
#

Extract the resulting value if there are no necessary effects.

valueliftSelect :: f a -> Select f a
#

Lift a functor into a free selective computation.

valuerunSelect :: Selective g => (forall x. f x -> g x) -> Select f a -> g a
#

Given a natural transformation from f to g, this gives a canonical natural transformation from Select f to g.