I think I do understand the list monad but then I found I am not. Here is the story.

Given list m and function k

> let m = [1..10]
> :t m
m :: [Integer]

> let k = replicate 2
> :t k
k :: a -> [a]

Playing with bind >>= give what I expect

> :t (>>=)
(>>=) :: Monad m => m a -> (a -> m b) -> m b
> :t m >>= k
m >>= k :: [Integer]
> m >>= k
[1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10]

but for >>

Expected (from experiencing with IO monad, everything on left side would be discarded)

m >> m
[1,2,3,4,5,6,7,8,9,10]

Got

> :t (>>)
(>>) :: Monad m => m a -> m b -> m b
:t m >> m
m >> m :: [Integer]
> m >> m
[1,2,3,4,5,6,7,8,9,10,1,2,3,4,5 ... 9,10] -- truncated, real output is 100 elements

Please explain why >> is not behave like I expected (of course I must have misunderstanding) and what is the correct way to interpret >> ?

list haskell monads
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