“[spreadsheet users] perceive themselves as better programmers than us and they’re not entirely wrong”

Functional programming in Excel.

Everyone tries to explain monads but very few succeed. I think this article is by far the most successful attempt I’ve read. I think I might be starting to get it.

Although not exactly the same, Promises and Observables work in a very similar way to monads. This becomes particularly evident when you look at chains of promises (which use a then() operator as “bind”.)

Observables are more like Haskell IO monads because they are lazy by design. None of the operations in an observable chain will run until something subscribes to it. All the functions must be pure but a running chain of Observables can do impure work such as making HTTP requests.