| Copyright | (c) Andy Gill 2001 (c) Oregon Graduate Institute of Science and Technology 2002 |
|---|---|
| License | BSD-style (see the file libraries/base/LICENSE) |
| Maintainer | libraries@haskell.org |
| Stability | experimental |
| Portability | portable |
| Safe Haskell | Trustworthy |
| Language | Haskell2010 |
Control.Monad.Fix
Description
Monadic fixpoints.
For a detailed discussion, see Levent Erkok's thesis, Value Recursion in Monadic Computations, Oregon Graduate Institute, 2002.
Documentation
class Monad m => MonadFix m where Source #
Monads having fixed points with a 'knot-tying' semantics.
Instances of MonadFix should satisfy the following laws:
- purity
mfix(return. h) =return(fixh)- left shrinking (or tightening)
mfix(\x -> a >>= \y -> f x y) = a >>= \y ->mfix(\x -> f x y)- sliding
, for strictmfix(liftMh . f) =liftMh (mfix(f . h))h.- nesting
mfix(\x ->mfix(\y -> f x y)) =mfix(\x -> f x x)
This class is used in the translation of the recursive do notation
supported by GHC and Hugs.
Minimal complete definition
Methods
Instances
| MonadFix [] # | |
| MonadFix Maybe # | |
| MonadFix IO # | |
| MonadFix Par1 # | |
| MonadFix Last # | |
| MonadFix First # | |
| MonadFix Product # | |
| MonadFix Sum # | |
| MonadFix Dual # | |
| MonadFix NonEmpty # | |
| MonadFix Option # | |
| MonadFix Last # | |
| MonadFix First # | |
| MonadFix Max # | |
| MonadFix Min # | |
| MonadFix Identity # | |
| MonadFix ((->) r) # | |
| MonadFix (Either e) # | |
| MonadFix f => MonadFix (Rec1 f) # | |
| MonadFix (ST s) # | |
| MonadFix (ST s) # | |
| (MonadFix f, MonadFix g) => MonadFix ((:*:) f g) # | |
| MonadFix f => MonadFix (Alt * f) # | |
| MonadFix f => MonadFix (M1 i c f) # | |
| (MonadFix f, MonadFix g) => MonadFix (Product * f g) # | |