Introduce let-else statement
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chriskrycho
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Sep 27, 2024
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Thanks again for this! I added a section earlier in the book introducing |
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let-else statementlet-else statement
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This is not technically part of the 2024 Edition, since it is available on the 2021 edition as well, but it *will* be an important update for the 2024 Edition revision of the print book!
- Merge in changes from `main`, including moving the chapter. - Merge in newly-written introduction of `let-else` in the same section as the `if let` discussion. - Rewrap lines.
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jhpratt
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Dec 17, 2024
Update books ## rust-lang/book 21 commits in 9900d976bbfecf4e8124da54351a9ad85ee3c7f3..ad2011d3bcad9f152d034faf7635c22506839d58 2024-12-16 16:11:34 UTC to 2024-12-05 19:19:24 UTC - Ch. 10: clarify note about compiler errors and `'static` (rust-lang/book#4164) - Introduce `let`-`else` statement (rust-lang/book#3702) - Fix misleading explanation of comma in `$(),*` (rust-lang/book#3800) - ch18-03: Matching Named Variables: mention `if let`/`while let` (rust-lang/book#3110) - Ch. 4: Rephrase/clarify paragraph on reference scope (rust-lang/book#3688) - Simplify note about functions in ch13-01-closures.md (rust-lang/book#3699) - fix: make the reason more understandable (rust-lang/book#4074) - Fixed grammatical error in the comment on line 22 (rust-lang/book#3180) - ch17-02: Monomorphization applies to generics in general (rust-lang/book#3367) - Ch. 21: Use `Vec::drain` to teach alternatives to `Option` (rust-lang/book#4159) - fix(typo): correct punctuation in ch15-06-reference-cycles.md (rust-lang/book#4155) - Ch. 20: show both `impl Fn` and `Box<dyn Fn>` (rust-lang/book#4152) - Add `use super::*;` to unit-test examples. (rust-lang/book#4151) - Remove emphasis on four-space indents (rust-lang/book#4150) - Fix `.git-blame-ignore-revs` file (rust-lang/book#4149) - Rust 2024: distinguish `unsafe fn` vs. `unsafe` blocks (rust-lang/book#4148) - Update README.md typo (rust-lang/book#4146) - Ch. 15.5: account for improved error message (rust-lang/book#4142) - Document use of rustfmt and dprint for formatting (rust-lang/book#4138) - tools: fix nostarch build reference to mdbook-trpl (rust-lang/book#4137) - Revise sentence to not refer to two subjects as it (rust-lang/book#4136) ## rust-lang/edition-guide 4 commits in 128669297c8a7fdf771042eaec18b8adfaeaf0cd..f56c9ae2d5b4344367e96513aea9eafb33c897e4 2024-12-10 21:29:01 UTC to 2024-12-04 21:24:35 UTC - Show tail expression temporary example that fails in 2024 (rust-lang/edition-guide#345) - Add more triagebot labeling support (rust-lang/edition-guide#346) - 2024: Assignment operator RHS indentation (rust-lang/edition-guide#341) - 2024: Add chapter on single-line `where` clauses (rust-lang/edition-guide#340) ## rust-lang/nomicon 1 commits in 0674321898cd454764ab69702819d39a919afd68..97e84a38c94bf9362b11284c20b2cb4adaa1e868 2024-12-10 02:41:27 UTC to 2024-12-10 02:41:27 UTC - races.md: data race -> race condition to violate memory safety (rust-lang/nomicon#470) ## rust-lang/reference 4 commits in ede56d1bbe132bac476b5029cd6d7508ca9572e9..183dd4b95f35dce35527d9fe68d869ac35e640e3 2024-12-14 21:22:49 UTC to 2024-12-06 03:21:54 UTC - Describe async closures (rust-lang/reference#1692) - Update closures for edition 2021 disjoint closure capturing (rust-lang/reference#1521) - Fix paragraphs with trailing `\1` (rust-lang/reference#1696) - Add triagebot autolabel (rust-lang/reference#1694) ## rust-lang/rust-by-example 1 commits in e1d1f2cdcee4d52b9a01ff7c448be4372a377b70..76406337f4131253443aea0ed7e7f451b464117c 2024-12-07 00:24:30 UTC to 2024-12-07 00:24:30 UTC - Fix rust-lang#1900 (rust-lang/rust-by-example#1901) ## rust-lang/rustc-dev-guide 9 commits in b21d99b..7f7ba48f04abc2ad25e52f30b5e2bffa286b019f 2024-12-16 07:12:01 UTC to 2024-12-05 05:01:46 UTC - Specify what a CGU is (rust-lang/rustc-dev-guide#2163) - functionality removed from codebase (part 2) (rust-lang/rustc-dev-guide#2160) - functionality removed from codebase (rust-lang/rustc-dev-guide#2159) - remove polymorphization (rust-lang/rustc-dev-guide#2158) - squashing: recommend --keep-base when squashing without a conflict (rust-lang/rustc-dev-guide#2157) - update section even more (rust-lang/rustc-dev-guide#2156) - extend closure constraints section (rust-lang/rustc-dev-guide#2155) - Remove `//@ compare-output-lines-by-subset` directive (rust-lang/rustc-dev-guide#2151) - Document `needs-target-has-atomic` directive (rust-lang/rustc-dev-guide#2154)
jhpratt
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to jhpratt/rust
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Dec 19, 2024
Update books ## rust-lang/book 21 commits in 9900d976bbfecf4e8124da54351a9ad85ee3c7f3..ad2011d3bcad9f152d034faf7635c22506839d58 2024-12-16 16:11:34 UTC to 2024-12-05 19:19:24 UTC - Ch. 10: clarify note about compiler errors and `'static` (rust-lang/book#4164) - Introduce `let`-`else` statement (rust-lang/book#3702) - Fix misleading explanation of comma in `$(),*` (rust-lang/book#3800) - ch18-03: Matching Named Variables: mention `if let`/`while let` (rust-lang/book#3110) - Ch. 4: Rephrase/clarify paragraph on reference scope (rust-lang/book#3688) - Simplify note about functions in ch13-01-closures.md (rust-lang/book#3699) - fix: make the reason more understandable (rust-lang/book#4074) - Fixed grammatical error in the comment on line 22 (rust-lang/book#3180) - ch17-02: Monomorphization applies to generics in general (rust-lang/book#3367) - Ch. 21: Use `Vec::drain` to teach alternatives to `Option` (rust-lang/book#4159) - fix(typo): correct punctuation in ch15-06-reference-cycles.md (rust-lang/book#4155) - Ch. 20: show both `impl Fn` and `Box<dyn Fn>` (rust-lang/book#4152) - Add `use super::*;` to unit-test examples. (rust-lang/book#4151) - Remove emphasis on four-space indents (rust-lang/book#4150) - Fix `.git-blame-ignore-revs` file (rust-lang/book#4149) - Rust 2024: distinguish `unsafe fn` vs. `unsafe` blocks (rust-lang/book#4148) - Update README.md typo (rust-lang/book#4146) - Ch. 15.5: account for improved error message (rust-lang/book#4142) - Document use of rustfmt and dprint for formatting (rust-lang/book#4138) - tools: fix nostarch build reference to mdbook-trpl (rust-lang/book#4137) - Revise sentence to not refer to two subjects as it (rust-lang/book#4136) ## edition-guide 6 commits in 128669297c8a7fdf771042eaec18b8adfaeaf0cd..bc4ce51e1d4dacb9350a92e95f6159a42de2f8c6 2024-12-03 22:02:43 +0000 to 2024-12-18 05:34:59 +0000 - Add chapter for 2024 match ergonomics reservations (rust-lang/edition-guide#349) - Re-title "Additions to the prelude" (rust-lang/edition-guide#348) - Show tail expression temporary example that fails in 2024 (rust-lang/edition-guide#345) - Add more triagebot labeling support (rust-lang/edition-guide#346) - 2024: Assignment operator RHS indentation (rust-lang/edition-guide#341) - 2024: Add chapter on single-line `where` clauses (rust-lang/edition-guide#340) ## rust-lang/nomicon 1 commits in 0674321898cd454764ab69702819d39a919afd68..97e84a38c94bf9362b11284c20b2cb4adaa1e868 2024-12-10 02:41:27 UTC to 2024-12-10 02:41:27 UTC - races.md: data race -> race condition to violate memory safety (rust-lang/nomicon#470) ## reference 8 commits in ede56d1bbe132bac476b5029cd6d7508ca9572e9..9f41bc11342d46544ae0732caf14ec0bcaf27376 2024-12-03 22:26:55 +0000 to 2024-12-18 23:04:30 +0000 - `coverage` attribute (rust-lang/reference#1628) - Clarify that `extern crate foo as føø` is allowed (rust-lang/reference#1697) - Fix rule auto-linking on Windows (rust-lang/reference#1698) - Reflect rust#133422 & rust#133587 to inline assembly documentation (rust-lang/reference#1695) - Describe async closures (rust-lang/reference#1692) - Update closures for edition 2021 disjoint closure capturing (rust-lang/reference#1521) - Fix paragraphs with trailing `\1` (rust-lang/reference#1696) - Add triagebot autolabel (rust-lang/reference#1694) ## rust-lang/rust-by-example 1 commits in e1d1f2cdcee4d52b9a01ff7c448be4372a377b70..76406337f4131253443aea0ed7e7f451b464117c 2024-12-07 00:24:30 UTC to 2024-12-07 00:24:30 UTC - Fix rust-lang#1900 (rust-lang/rust-by-example#1901) ## rust-lang/rustc-dev-guide 9 commits in b21d99b..7f7ba48f04abc2ad25e52f30b5e2bffa286b019f 2024-12-16 07:12:01 UTC to 2024-12-05 05:01:46 UTC - Specify what a CGU is (rust-lang/rustc-dev-guide#2163) - functionality removed from codebase (part 2) (rust-lang/rustc-dev-guide#2160) - functionality removed from codebase (rust-lang/rustc-dev-guide#2159) - remove polymorphization (rust-lang/rustc-dev-guide#2158) - squashing: recommend --keep-base when squashing without a conflict (rust-lang/rustc-dev-guide#2157) - update section even more (rust-lang/rustc-dev-guide#2156) - extend closure constraints section (rust-lang/rustc-dev-guide#2155) - Remove `//@ compare-output-lines-by-subset` directive (rust-lang/rustc-dev-guide#2151) - Document `needs-target-has-atomic` directive (rust-lang/rustc-dev-guide#2154)
rust-timer
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Dec 19, 2024
Rollup merge of rust-lang#134388 - rustbot:docs-update, r=ehuss Update books ## rust-lang/book 21 commits in 9900d976bbfecf4e8124da54351a9ad85ee3c7f3..ad2011d3bcad9f152d034faf7635c22506839d58 2024-12-16 16:11:34 UTC to 2024-12-05 19:19:24 UTC - Ch. 10: clarify note about compiler errors and `'static` (rust-lang/book#4164) - Introduce `let`-`else` statement (rust-lang/book#3702) - Fix misleading explanation of comma in `$(),*` (rust-lang/book#3800) - ch18-03: Matching Named Variables: mention `if let`/`while let` (rust-lang/book#3110) - Ch. 4: Rephrase/clarify paragraph on reference scope (rust-lang/book#3688) - Simplify note about functions in ch13-01-closures.md (rust-lang/book#3699) - fix: make the reason more understandable (rust-lang/book#4074) - Fixed grammatical error in the comment on line 22 (rust-lang/book#3180) - ch17-02: Monomorphization applies to generics in general (rust-lang/book#3367) - Ch. 21: Use `Vec::drain` to teach alternatives to `Option` (rust-lang/book#4159) - fix(typo): correct punctuation in ch15-06-reference-cycles.md (rust-lang/book#4155) - Ch. 20: show both `impl Fn` and `Box<dyn Fn>` (rust-lang/book#4152) - Add `use super::*;` to unit-test examples. (rust-lang/book#4151) - Remove emphasis on four-space indents (rust-lang/book#4150) - Fix `.git-blame-ignore-revs` file (rust-lang/book#4149) - Rust 2024: distinguish `unsafe fn` vs. `unsafe` blocks (rust-lang/book#4148) - Update README.md typo (rust-lang/book#4146) - Ch. 15.5: account for improved error message (rust-lang/book#4142) - Document use of rustfmt and dprint for formatting (rust-lang/book#4138) - tools: fix nostarch build reference to mdbook-trpl (rust-lang/book#4137) - Revise sentence to not refer to two subjects as it (rust-lang/book#4136) ## edition-guide 6 commits in 128669297c8a7fdf771042eaec18b8adfaeaf0cd..bc4ce51e1d4dacb9350a92e95f6159a42de2f8c6 2024-12-03 22:02:43 +0000 to 2024-12-18 05:34:59 +0000 - Add chapter for 2024 match ergonomics reservations (rust-lang/edition-guide#349) - Re-title "Additions to the prelude" (rust-lang/edition-guide#348) - Show tail expression temporary example that fails in 2024 (rust-lang/edition-guide#345) - Add more triagebot labeling support (rust-lang/edition-guide#346) - 2024: Assignment operator RHS indentation (rust-lang/edition-guide#341) - 2024: Add chapter on single-line `where` clauses (rust-lang/edition-guide#340) ## rust-lang/nomicon 1 commits in 0674321898cd454764ab69702819d39a919afd68..97e84a38c94bf9362b11284c20b2cb4adaa1e868 2024-12-10 02:41:27 UTC to 2024-12-10 02:41:27 UTC - races.md: data race -> race condition to violate memory safety (rust-lang/nomicon#470) ## reference 8 commits in ede56d1bbe132bac476b5029cd6d7508ca9572e9..9f41bc11342d46544ae0732caf14ec0bcaf27376 2024-12-03 22:26:55 +0000 to 2024-12-18 23:04:30 +0000 - `coverage` attribute (rust-lang/reference#1628) - Clarify that `extern crate foo as føø` is allowed (rust-lang/reference#1697) - Fix rule auto-linking on Windows (rust-lang/reference#1698) - Reflect rust#133422 & rust#133587 to inline assembly documentation (rust-lang/reference#1695) - Describe async closures (rust-lang/reference#1692) - Update closures for edition 2021 disjoint closure capturing (rust-lang/reference#1521) - Fix paragraphs with trailing `\1` (rust-lang/reference#1696) - Add triagebot autolabel (rust-lang/reference#1694) ## rust-lang/rust-by-example 1 commits in e1d1f2cdcee4d52b9a01ff7c448be4372a377b70..76406337f4131253443aea0ed7e7f451b464117c 2024-12-07 00:24:30 UTC to 2024-12-07 00:24:30 UTC - Fix rust-lang#1900 (rust-lang/rust-by-example#1901) ## rust-lang/rustc-dev-guide 9 commits in b21d99b..7f7ba48f04abc2ad25e52f30b5e2bffa286b019f 2024-12-16 07:12:01 UTC to 2024-12-05 05:01:46 UTC - Specify what a CGU is (rust-lang/rustc-dev-guide#2163) - functionality removed from codebase (part 2) (rust-lang/rustc-dev-guide#2160) - functionality removed from codebase (rust-lang/rustc-dev-guide#2159) - remove polymorphization (rust-lang/rustc-dev-guide#2158) - squashing: recommend --keep-base when squashing without a conflict (rust-lang/rustc-dev-guide#2157) - update section even more (rust-lang/rustc-dev-guide#2156) - extend closure constraints section (rust-lang/rustc-dev-guide#2155) - Remove `//@ compare-output-lines-by-subset` directive (rust-lang/rustc-dev-guide#2151) - Document `needs-target-has-atomic` directive (rust-lang/rustc-dev-guide#2154)
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This PR mentions the
let-elsestatement as an example of language construct that can accept both refutable and irrefutable patterns.