Safe Haskell	None
Language	GHC2021

Control.Memo.Fix

Synopsis

memoFix :: Int -> ((Int -> a) -> Int -> a) -> Int -> a
memoFixMap :: Ord k => ((k -> State (Map k a) a) -> k -> State (Map k a) a) -> k -> a
memoFixIntMap :: ((Int -> State (IntMap a) a) -> Int -> State (IntMap a) a) -> Int -> a

Documentation

memoFix Source #

Arguments

:: Int	memo size
-> ((Int -> a) -> Int -> a)
-> Int
-> a

>>> :set -XLambdaCase
>>> :{
let memoFib = \fib -> \case
      0 -> 0
      1 -> 1
      i -> fib (i - 1) + fib (i - 2)
 in memoFix 100 memoFib 50
:}
12586269025

memoFixMap :: Ord k => ((k -> State (Map k a) a) -> k -> State (Map k a) a) -> k -> a Source #

>>> :set -XLambdaCase
>>> :{
let memoFibM :: (Monad m) => (Int -> m Integer) -> Int -> m Integer
    memoFibM = \fib -> \case
      0 -> pure 0
      1 -> pure 1
      i -> (+) <$> fib (i - 1) <*> fib (i - 2)
 in memoFixMap memoFibM 50
:}
12586269025

memoFixIntMap :: ((Int -> State (IntMap a) a) -> Int -> State (IntMap a) a) -> Int -> a Source #

>>> :set -XLambdaCase
>>> :{
let memoFibM :: (Monad m) => (Int -> m Integer) -> Int -> m Integer
    memoFibM = \fib -> \case
      0 -> pure 0
      1 -> pure 1
      i -> (+) <$> fib (i - 1) <*> fib (i - 2)
 in memoFixIntMap memoFibM 50
:}
12586269025