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Comment by kinofcain | Hacker News Reader

I'm beginning to think that all the people who have ever understood monads have written an article trying to explain them.

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I understand monads and use them everyday, but I've never written an article about them. I did once try to explain to someone what a monad is... that could be the reason I've never tried.

You should write an article!

I'll start with the continuation monad, explaining that via the Curry-Howard correspondence it is related to a double negative. I'll go on to show that the continuation monad is more general than any other monad by showing how to implement some common ones (state, list, IO, coroutines) using it. I'll finish with a half-baked analogy.

Write a program which generates explanations of monads. By the time Haskell compiles it, it will be provably correct without the need for tests.

I understand monads and use them everyday,

Same thing here and I am not writing a tutorial, because good tutorials already exist. For example:

http://blog.sigfpe.com/2006/08/you-could-have-invented-monad... http://www.manning.com/bjarnason/

In fact, the latter book lets you write your own functors and monads without even telling you, and then shows you that you actually already understand these concepts.

Only three kinds of people have ever understood Monads - some of them died, others went mad trying to formulate explanations and the rest have forgotten all about them.

And that somehow in understanding monads, the lose the capability of explaining them.

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