Yet Another Monad Tutorial (part 3: The Monad Laws)

[mvanier]

In the previous article I talked about the two fundamental monadic operations in the Monad type class: the bind operator (>>=) and the return function. In this article I'll complete the definition of the Monad type class and talk about monad laws.

Comments

Suggestion

[anonymous]

Sticking with the "repetition pedagogy", I would remind the reader of ">>=" being kind of a pipe "|" as in linux' shell, which I assume every reader knows. I personally had to recall this each time I read the symbol ">>=" since it's not a really intuitive symbol to me.

Re: Suggestion

[mvanier]

This is a good point and when I discuss this operator in class I mention Unix pipes. Since you've just mentioned it for me, you've saved me the trouble! ;-)

[sovkista]

Hi!

-- Form 1.
-- mv :: m a
-- f :: a -> m b

mv >>= \x -> mf x

Maybe
mv >>= \x -> f x ?

I can't figure out why we have mf here,

Typo

[mvanier]

That was a typo, which I just fixed. Thanks!