Haskell's missing mutable reference type

BurningWitness:

Not exactly, my point is that tacking dynamic allocations onto this feature is at best unnecessary and at worst would pollute the language with a second way to do something it already excels at.

I don’t understand. What is “this feature”? Your “contextual”?

BurningWitness:

A static reference table is the “missing” thing in the language as I see it.

OK, fine, and if that missing thing is added, I’ll add the API that I want on top. What’s wrong with that?

BurningWitness:

tomjaguarpaw:

With “references”, the libraries providing Logger and writeUserData need not know anything about the existence of “references”. Only the caller need use them.

I don’t think this has anything to do with whether the references are static or dynamic, you can wrap the library either way.

I agree. But you said “With references the library would declare an implicit configuration” (my emphasis). I’m pointing out it’s not the library that declares the implicit configuration, it’s the caller.