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Comment by edvinbesic | Hacker News Reader

Taking a cursory look at their example, and this caught my eye:

    supervisor
      .broadcast("A message containing data.")
      .expect("Couldn't broadcast the message.");

As a non-native English speaker, the word expect tricks me up here. Is this use correct?

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I think the recommendation is to phrase the error message that is given to .expect() not as what went wrong but as what we had expected to happen.[1] If the example that you show was consistent with that recommendation, it might look like this:

    supervisor
      .broadcast("A message containing data.")
      .expect("message broadcast should not fail");

Although even if you are a native English speaker, this is dubious improvement if you don’t know what Option types are and what .expect() does with them.

[1] https://doc.rust-lang.org/std/option/enum.Option.html#recomm...

That's standard Rust error-handling code: it prints an error message and panics out (if I remember correctly, I haven't touched Rust in years).

"I found Rust when no one heard of them, man. They really knew how to put on a show back then. Now, they're so mainstream and commercial, I'm over 'em. Their latest album is so pop. I heard from their managers that brainfuck and Zig are touring this year." <- Hipsters on music

; @ D

expect() is an assertion of non-failure. The string is the panic message on failure.

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