Labeled switch documentation #21383
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Labeled switch documentation #21383
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This feature was proposed in ziglang#8220, and implemented in ziglang#21257.
After testing, `break` does not target an unlabeled `switch`. However, it *can* target a labeled switch, even if the `break` is unlabeled. This behavior seems surprising and worth a callout, although this may not be the place for it.
This paragraph was copied from the release notes, written by @mlugg.
As before, text has been adapted from the release notes, which were written by @mlugg.
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LiterallyVoid
commented
Sep 11, 2024
LiterallyVoid
commented
Sep 11, 2024
LiterallyVoid
commented
Sep 11, 2024
Oh shit, that's definitely a bug, thank you for pointing it out. I'll get a fix up shortly. EDIT: see #21385 |
I'm also moving away from "statement" here. Break is actually an
expression, and while it's almost impossible to observe this in code
that doesn't have any compiler errors, it can be shown:
test "a" {
_ = while (true) {
_ = break 42;
};
}
Nevertheless, `break` is still described as a statement in the Zig
docs. It may be that the Zig docs simply take statement to mean
something else---it says, "compile log statements", later in the
document.
I've tried to cram as many concepts in as few lines as possible. I've also split the desugaring into its own test---the names here are bad, and I'll improve them soon.
This comment was moved here from the other switch continue example, as that one no longer shows switch having a result value.
andrewrk
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Sep 13, 2024
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Feel free to nitpick wording and examples, especially mine---the good parts have been copied from @mlugg's release notes!
In particular, I found that you're able to break out of a switch with an unlabeled break. This was really surprising, and may be better disallowed than noted in the docs.
Closes #21375