js-proposal-algebraic-effects VS rustic_result

I have to admit: you're perfectly right here. React of course always relied on mutable state in it's implementation – just so we don't have to. I derailed a lot here to keep this funny thread going ;) I'm still not with you on your definition of "functional", since you treated it synonymously with "purely functional". Functional means just made by applying and composing functions, and react UI is created exactly like that. There is an awesome algebraic effects proposal[1], which will hopefully will be added to JavaScript one day, then react will make use of it to become purely functional.

1: https://github.com/macabeus/js-proposal-algebraic-effects

Super interesting, there is a proposal to add this to JavaScript and several languages that use this, unison, koka & eff. I had no idea this was even a thing!

Ok I was wrongly assuming that panic was expecting an error type, in fact it's an interface{}.

> Your use of exceptions for flow control (i.e. goto) is considered harmful

Exceptions are a way to delegate error handling to the caller by giving them informations about the unexpected behavior. It implies that the expected behavior is the "happy path" (everything went well) and any deviations (errors) is unexpected.

This is far from a goto because you can have `try/finally` blocks without catch (or defer in golang).

Also, exceptions are just a kind of algebraic effects that do not resume. There was a proposal to JS for this: https://github.com/macabeus/js-proposal-algebraic-effects

This is also easier to test. assertRaises(ErrorType, func() { code... })

Almost every Go library I've seen just return an error (which is just a string), you'd need to parse it to assert that the correct error is returned in special conditions.

Self promotion moment:

If you enjoy the Result/Either type and API in Rust, I made this project just for this: https://github.com/linkdd/rustic_result

I also made https://github.com/linkdd/rustic_maybe/tree/main for an Option/Maybe type.

NB: Those are not types, but I'm waiting for set theoretic types to update those libs :)

It's missing the Erlang/Elixir pattern of returning a tuple `{:ok, T}` or `{:error, E}`, where we can then use pattern matching, or `with` expressions, etc...

To be fair, it is very similar to a `Result` type, which is why I made this library a while ago: https://github.com/linkdd/rustic_result

I intend to add a pipeline operator similar to Elixir, to be used with an std::result module which will provide functions to ease writing such complex code. I may take inspiration on an Elixir library I wrote a while ago: https://github.com/linkdd/rustic_result

A while ago, I made this library https://github.com/linkdd/rustic_result

I also made a library for working with `{:ok, value}` and `{:error, reason}` in Elixir: https://github.com/linkdd/rustic_result

Thanks to the pipeline operator and pattern matching, it makes pretty easy to read pipelines. It does not completely replace the with statement (that was not the point) but it simplified a lot of code.