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by ddellacosta 4164 days ago
I don't know if I can agree with this. I've invested a significant amount of time in learning about monads (and functors, applicatives, monoids, and more from the bestiary of commonly used category theoretic structures in Haskell) and I find them quite challenging to grasp in their full generality. While specific use-cases are readily understood, getting to the heart of what a monad "is" has taken me time, and I honestly don't believe I've properly grasped it yet.

So I think there's a spectrum of understanding and effective use when it comes to monads and other algebraic structures like these, and I'm skeptical when people say, "oh yeah, a monad is just X, it's simple." I've said that myself in the past and I was wrong, and so were most of the people I've heard say that.

To put it another way: when I hear people who know what they're talking about say it's simple, they are talking about its structure, not about understanding what it is and how it is used. In that sense it is quite simple. But as Euclid said, there's no royal road to geometry (er, or monads...).
1 comments
dkersten 4163 days ago
Absolutely there's a spectrum and I certainly don't fully understand the full set of category theoretic structures (I'm slowly trying to learn, but.. its slow going). I just think that monads as programming constructs are quite simple. I don't doubt that in a full mathematical context there is a hell of a lot more to them and the mathematical reasoning behind how they work is surely beyond my understanding, but from a how they work, how to use them, how they interact with the language and what they enable you to do point of view, they aren't difficult at all.
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ddellacosta 4163 days ago
...but from a how they work, how to use them, how they interact with the language and what they enable you to do point of view, they aren't difficult at all.

I guess we'll have to agree to disagree here: I have found it challenging to grasp all of these things (even simply within the context of programming language usage). I guess that is, in the end, rather subjective.

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