Untitled

spanM, takeWhileM in Haskell
Prelude Control.Monad.Loops> let xs = ["a", "bb", "ccc", "dddd", "eeeee"]
Prelude Control.Monad.Loops> let f x = putStrLn x >> return (length x)
Prelude Control.Monad.Loops> let p x = x < 2
Prelude Control.Monad.Loops> allM (fmap p . f) xs
a
bb
False

process :: [IO Int] -> IO Bool
process []     = return True
process [a]    = a >> return True
process (a:as) = do
    n <- a
    if n > 0
        then return False
        else process as

import Control.Monad.ListM

process :: [IO Int] -> IO Bool
process as = do
  taken <- takeWhileM (>>= return . (<= 0)) as
  return (length taken >= length as - 1)