What's in the Box?

Re:What's in the Box? by valand on Tuesday April 20, 2021 @01:29AM (#26871016)

> Because in JavaScript, if something goes wrong, we just throw!

A bit out of topic: somewhat ironic that the JS/TS-based projects in my workplace we ended up using return and Result<T, E>-like struct, backed by TypeScript's union type.

Throws is only for never-scenarios and unhandled cases.

Rust-like approach has been very successful to squash runtime bugs, especially in big, complex products.

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Re:What's in the Box? by rattray on Wednesday April 21, 2021 @12:44AM (#26885501)

I really like this pattern in TS:

    const x: Data | Error = await fetchData().catch(e => e);
    if (x instanceof Error) {
      return 'too bad'
    }
    // proceed with x as Data

Basically you add `.catch(e => e)` to any I/O which may fail, and handle the error in an `if` instead of a `try`.

Many of the benefits of Go's error handling, but without the awkward extra variable and without a chance of using your result without ensuring it isn't an error.

[ Parent | on HN ]