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Comment by _hardwaregeek | Hacker News Reader

It's error prone in that you aren't forced to handle the error. In languages such as Rust or Haskell, you have a Result type which can either be an Ok(val) or an Err(err). In order to "unwrap" a Result, you have to check the error case. Basically there's a compile time guarantee that errors are handled.

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I'm not a Rust expert but afaik Rust doesn't enforce error checking since you explicitly need to unwrap(). It's very possible to panic because you forgot to check something.

It's similar in Go since you can't compile with unused variable so you need to explicitly discard the error with _. Ex: result, _ := func() This is for multi-value returns, for single value you can even omit the _

https://golang.org/doc/effective_go.html#blank

Having unwrap() in your Rust code is like littering your code base with panic(). It’s not appropriate to use in most production code, but is convenient in prototypes, examples and tests.

Your example re Go errors is incorrect. The go compiler allows you to ignore errors in returns without any compiler error.

For example

err := doThingThatErrs()

and

doThingThatErrs()

are both valid Go code.

There's nothing wrong with unwrap. It's just an assert. Even a[i] is just shorthand for a.get(i).unwrap(). Asserts are definitely appropriate in production code, just not for handling run-time errors.

Then how is this better than anything else? Except for syntactical sugar for:

Try Return [Bla(), null] Catch err Return [null, err] End

I do like this syntax better, bc the different scopes cause a lot of nesting

My example is correct I explained all of that, multi values -> need to omit, single value can ignore everything.

Yup. I misspoke. We’re both right.

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