DouKaku? 2110 nskj77: こんな感じ。 *Main> f ...(与えた条件を満たす候補)

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こんな感じ。
*Main> f ["and","or","not","and"]
(True,True,True,True)
(True,True,False,True)
(True,False,False,True)
(False,True,False,True)
(False,False,False,True)

t :: (Bool -> Bool) -> [Bool] -> [String] -> Bool
t prev (x:[]) _ = prev x
t prev (x:xs) (op:ops) | op == "not" = t prev (not x:xs) ops
                       | op == "and" = t ((&&) (prev x)) xs ops
                       | op == "or"  = t ((||) (prev x)) xs ops

f :: [String] -> IO ()
f ops = mapM_ print [(b1,b2,b3,b4) | bs@(b1:b2:b3:[b4]) <- bss, test bs ops]
  where bss = sequence $ replicate 4 [True,False]
        test = t id

guard をつかってみた

import Control.Monad

starling f g x = f x (g x)

f :: [String] -> [[Bool]]
f cs = sequence (replicate 4 [False,True])
   >>= starling ((>>) . guard . flip (t id) cs) return

t :: (Bool -> Bool) -> [Bool] -> [String] -> Bool
t prev [x]    _           = prev x
t prev (x:xs) ("not":ops) = t prev (not x:xs) ops
t prev (x:xs) ("and":ops) = t (prev x &&) xs  ops
t prev (x:xs) ("or" :ops) = t (prev x ||) xs  ops

{-
*Main> f ["and","or","not","and"]
[[False,False,False,True]
,[False,True,False,True]
,[True,False,False,True]
,[True,True,False,True]
,[True,True,True,True]]
-}

関数型っぽいですね。
foldl を使って写経。（test の部分のみ）

test xs ops = p x where
  (p, x:_) = foldl f (id, xs) ops
  f (prev, x:xs) op
    | op == "not" = (prev, not x:xs)
    | op == "and" = (((&&) (prev x)), xs)
    | op == "or" = (((||) (prev x)), xs)

DouKaku?

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