badrap / result

A TypeScript result type taking cues from Rust's Result and Haskell's Either types
MIT License
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Thoughts on an orElse/unwrapOrElse equivalent? #23

Open abrenneke opened 1 year ago

abrenneke commented 1 year ago

I'm liking the lib so far! What are your thoughts on orElse methods? Right now if I want to have errors fallback I do:

const res = fn().chain(
  (x) => Result.ok(x),
  () => otherFn()
);

But that could be made a little more ergonomic if it was something like:

const res = fn().orElse((err) => otherFn());

Or the equivalent unwrap:

const val = fn().unwrapOrElse((err) => otherFn());

I get that it's a balance of keeping the lib small and having things be ergonomic - rust has soo many Result methods 😆

sam-mfb commented 3 months ago

how would unwrapOrElse work? what would be the type of val in an error scenario?

is the idea that unwrapOrElse would always throw in the error case? if not, how do you handle the fact that val continues to live on in outer scope in an error situation?

i like the idea of these ergonomics but i don't see anyway to not return control to the outer scope unless you are always throwing after otherFn() is called.