[lmm]

You don't really need language features, assuming your language has sum types, polymorphism and first class functions (and why bother using a language that's missing any of those). All you need is some functions, and you can write those yourself since they're just functions. https://fsharpforfunandprofit.com/posts/recipe-part2/

[saghm]

> You don't really need language features, assuming your language has sum types, polymorphism and first class functions (and why bother using a language that's missing any of those).

To be fair, this is basically saying "you don't need language features as long as you have these language features".

[lmm]

Sure, but those are general language features that you'd want to have for many other reasons anyway. You don't need any option/result-specific language features.

[JackFr]

> You don't really need language features, assuming your language has sum types, polymorphism and first class functions

Aren’t those features?

[lmm]

My point is that Option::ok_or and Option::map aren't language features, they're just plain old functions written in the language; if they weren't there you could implement them yourself. You need some language features to implement them (e.g. you can't implement map without first-class functions), but those are general-purpose language features that you'd want to have anyway.