graydon2 | things rust shipped without
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  • TehPers@beehaw.orgEnglish
    0·
    1 year ago

    Their suggested replacement is closer to C#'s is keyword:

    if foo is Some(foo) {
    // ...
}

    The issue here is that we still have let-else, which can’t be translated as easily:

    let Some(foo) = foo else {
    todo!();
};
      • TehPers@beehaw.orgEnglish
        0·
        1 year ago

        That’s not an alternative, it’s removing let-else entirely. It’s equivalent to this:

        let i = if let Some(i) = opt_number {
    i
} else {
    return 0;
};

        let-else is specifically a feature that allows you to use a refutable pattern to deconstruct a value by providing a diverging else branch.