Bind and function composition

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#1

I have come across the following law about bind and function composition o:

“bind m (f o g) = f (bind m g)”

It type checks but why is it true? Is there any literature on this?

#2

Is that law true?? Consider the following trivial example

main :: IO ()
main = do 
  print (ma >>= (f . g))
  print (f (ma >>= g))


f :: Maybe a -> Maybe Int
f _  = Just 0

g = Just

ma = Nothing

-- returns
>
Nothing
Just 0
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