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Comment by gitgud | Hacker News Reader

The logging example reminds me of Aspect Oriented Programming, where you inject less-important things like logging into the programming using decorators. There's a few libraries that do that for c# not sure about the f# ecosystem though.

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Algebraic effect systems can also do this. See Koka, Eff, Multicore OCaml, Frank, Purescript-run, freer-effects, freer-simple etc. These generally allow you to handle effects in different ways. Not sure if F#'s type system is powerful enough to build this as a library though.

I took a look at Koka and it doesn't look like what I want because I have to correctly specify the effects whenever I write a function signature. What I am looking for is a type system that would track these "implicit dependencies" but not force me to pollute all my type signatures with them. In other words, if the compiler knows the type is

   function square3( x : int ) : div int

My code should be allowed say

   function square3( x : int ) : int

Basically, the problem is that in most typed languages, if you add a logger dependency to a function, then you have to rewrite the signatures of all the functions that depend on that function. That sucks.

Logging with computation expressions: https://fsharpforfunandprofit.com/posts/computation-expressi...

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