Add expect-like functionality to Result and Option

[gibbz00]

Reference: https://doc.rust-lang.org/std/result/enum.Result.html#method.expect

Implemented by adding an optional message string parameter for the respective unwraps.

[slavovojacek]

Why not also call this expect and implement it as per the Rust link you attached?

[gibbz00]

Good question, two things that go hand in hand.

I've always found expect to be counterintuitive, for example: option.expect("it to extist") will result in a panic message containing something similar to: "program panicked, unwrapped option: 'it to exist'". In other words: you call expect when you "expect" it to work, but supply the message to be shown when it doesn't. (Granted, I'm not the first one to voice this concern.)

Rust doesn't have operator overloading, so it might be one reason for why the naming is the way it is in the first place. JS/TS does, however, and I think this is a good case for when to apply it. It reduces the number of functions exposed, and it makes unwrapping more natural, even though the latter is of corue more of a personal opinion.

[slavovojacek]

Thanks for the explanation, makes sense. A few thoughts:

1. I am slightly concerned unwrap(errorMessage) might easily be misinterpreted to mean unwrap(defaultValue)
2. Given all other methods are named after their Rust equivalent I would lean towards following that convention despite the unfortunate naming - it's just one less translation step people have to go through when trying to link it back to the original implementation

Please let me know what you think!

[corbinu]

@slavovojacek I agree with keeping with Rust equivalents on this.