Add error explanation for E0491 #39091
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Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @pnkfelix (or someone else) soon. If any changes to this PR are deemed necessary, please add them as extra commits. This ensures that the reviewer can see what has changed since they last reviewed the code. Due to the way GitHub handles out-of-date commits, this should also make it reasonably obvious what issues have or haven't been addressed. Large or tricky changes may require several passes of review and changes. Please see the contribution instructions for more information. |
| Erroneous code example: | ||
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| ```compile_fail,E0491 | ||
| //struct containing a reference requires a lifetime parameter, |
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Please add a whitespace after the '//'.
| //struct containing a reference requires a lifetime parameter, | ||
| //because the data the reference points to must outlive the struct (see E0106) | ||
| struct Struct<'a> { | ||
| ref_i32: &'a i32 |
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Please add a comma at the end of the line.
| ref_i32: &'a i32 | ||
| } | ||
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| //However, a nested struct like this, the signature itself does not tell |
| //whether 'a outlives 'b or the other way around. | ||
| //So it could be possible that 'b of reference outlives 'a of the data. | ||
| struct Nested<'a, 'b> { | ||
| ref_struct: &'b Struct<'a> //compile error E0491! |
| ``` | ||
| "##, | ||
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Why so much empty lines?
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| //'a: 'b means 'a outlives 'b | ||
| struct Nested<'a: 'b, 'b> { | ||
| ref_struct: &'b Struct<'a> |
| ref_i32: &'a i32 | ||
| } | ||
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| //'a: 'b means 'a outlives 'b |
| struct Nested<'a, 'b> { | ||
| ref_struct: &'b Struct<'a> //compile error E0491! | ||
| ref_struct: &'b Struct<'a>, //compile error E0491! |
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Still missing a whitespace after '//'.
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Oh and the '!' isn't needed. ;)
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ah sorry, fixing this now...
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@GuillaumeGomez thank you very much for quick reviews. I think all your comments are reflected now. |
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Thanks! Now please squash your commits and it'll be good to go! |
| // 'a: 'b means 'a outlives 'b | ||
| struct Nested<'a: 'b, 'b> { | ||
| ref_struct: &'b Struct<'a>, | ||
| }F |
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Missed this one: Why is there an 'F' here?
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oops sorry, :| will delete this F and squash my commits
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Squashed into a single commit and removed the unnecessary 'F' as advised. |
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Thanks! @bors: r+ rollup |
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📌 Commit c525094 has been approved by |
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Is this still in change requested state? |
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Reviews status are just an indication, nothing to worry. I have put your PR in the bot's queue. It'll handle the tests and the merge for us. |
…on, r=GuillaumeGomez Add error explanation for E0491 Refs rust-lang#32777 Please let me know if any question or anything doesn't look right about this.
Refs #32777
Please let me know if any question or anything doesn't look right about this.