Improve chapter about Vec<T>
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The usage of `PhantomData<T>` in this chapter is wrong and useless. It's only needed when you have an unstable `#[may_dangle` on `Drop`. Since the `phantom-data` chapter talks about this extensively, link to it for more info and stop using `PhantomData<T>` for dropck in the vec chapter.
`mem::forget` should usually not be used in unsafe code, as it's a little footgunny. `mem::forget` does a typed move _after_ the type has been moved out of, which is bad, as typed moves assert validity, but types can become invalid once they have been moved out of. In this specific example it's not a soundness problem, but we should promote the better style of using `ManuallyDrop<T>` instead.
JohnTitor
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danielhenrymantilla
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| * We may own a value of type `T` (this is not relevant for our example here, but see | ||
| [the chapter on PhantomData][phantom-data] on why the real `std::vec::Vec<T>` needs this) |
Co-authored-by: Daniel Henry-Mantilla <[email protected]>
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Update books ## rust-lang/book 1 commits in 3f64052c048c6def93b94a2b514ee88bba918744..a60f4316ec923a5ac2ed6a2eba6960edb832d855 2022-11-16 15:07:18 UTC to 2022-11-16 15:07:18 UTC - Fix Install MdBook command (rust-lang/book#3424) ## rust-embedded/book 4 commits in c533348edd69f11a8f4225d633a05d7093fddbf3..19f798d448835a4888e3b3eae7fe69f1d61d8681 2022-11-17 15:08:11 UTC to 2022-11-08 23:27:57 UTC - start/hardware.md: Fix typo (rust-embedded/book#336) - doc: Fix `arm-none-eabi-gdb` installation instruction for Fedora 27 or newer to just use `gdb` (rust-embedded/book#335) - Update singletons.md (rust-embedded/book#334) - Remove incorrect claim HashMap is avail in no_std (rust-embedded/book#333) ## rust-lang/nomicon 2 commits in 05532356e7a4dbea2330aabb77611f5179493bb8..ae406aa5287a9e025abb72343aaceec98458c117 2022-11-21 22:48:20 UTC to 2022-11-15 00:29:20 UTC - Improve chapter about `Vec<T>` (rust-lang/nomicon#381) - Grammar change for 3.4: Limits of Lifetimes (lifetime-mismatch.md) (rust-lang/nomicon#386) ## rust-lang/reference 9 commits in 9f0cc13ffcd27c1fbe1ab766a9491e15ddcf4d19..3ae62681ff236d5528ef7c8c28ba7c6b2ecc6731 2022-12-05 00:51:50 UTC to 2022-11-15 20:43:30 UTC - Document that type parameter `Self` is unsized by default (rust-lang/reference#1285) - replace `crateid` term with `crate_name` (rust-lang/reference#1310) - Document native library modifier `verbatim` (rust-lang/reference#1299) - Update literal suffix docs for rust-lang#102944 (rust-lang/reference#1305) - update aliasing rules section of the reference (rust-lang/reference#1290) - Document RFC 2867: instruction_set attribute (rust-lang/reference#1253) - Fix a minor typo in the "Higher-ranked trait bounds" section (rust-lang/reference#1288) - Disallow newline directly following `//` (rust-lang/reference#1294) - Add an anchor to the "forwarding macro fragments" paragraph (rust-lang/reference#1300) ## rust-lang/rust-by-example 5 commits in 2b15c0abf2bada6e00553814336bc3e2d8399097..a9869b4a3c4cac3bc6099b41f088679e268400b8 2022-11-27 19:03:05 UTC to 2022-11-11 18:54:53 UTC - Migrate from highfive to triagebot (rust-lang/rust-by-example#1647) - Simpler version of the read_lines script. (rust-lang/rust-by-example#1641) - Fix comment in "Formatted print" example code (rust-lang/rust-by-example#1638) - Added a missing backtick in a comment in chapter 15.4. (rust-lang/rust-by-example#1642) - Clarify the confusing closure example rust-lang#1611 (rust-lang/rust-by-example#1643) ## rust-lang/rustc-dev-guide 13 commits in d0dc6c97a6486f68bac782fff135086eae6d77ec..e269950a57fa6fcda356426545fb5aa3691a7ced 2022-12-03 23:09:24 UTC to 2022-11-08 21:35:38 UTC - Remove duplicate paragraph (rust-lang/rustc-dev-guide#1523) - clarify subtree tool policy (rust-lang/rustc-dev-guide#1518) - Typo (rust-lang/rustc-dev-guide#1520) - Link directly to the section on `--keep-stage` (rust-lang/rustc-dev-guide#1515) - do an actual link to detect if it breaks in future (rust-lang/rustc-dev-guide#1517) - Triage some date-check items (rust-lang/rustc-dev-guide#1513) - Update path for `try_mark_green` implementation (rust-lang/rustc-dev-guide#1512) - Fix a broken design docs link about unused substs bug (rust-lang/rustc-dev-guide#1511) - updating-llvm: keep a calm tone (rust-lang/rustc-dev-guide#1449) - date-check: updating-llvm (rust-lang/rustc-dev-guide#1424) - rewrite the section about regions in the trait solver (rust-lang/rustc-dev-guide#1508) - Consistent ordered list indexing (rust-lang/rustc-dev-guide#1509) - Document multiple alternative suggestions on diagnostic structs (rust-lang/rustc-dev-guide#1486)
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Update books ## rust-lang/book 1 commits in 3f64052c048c6def93b94a2b514ee88bba918744..a60f4316ec923a5ac2ed6a2eba6960edb832d855 2022-11-16 15:07:18 UTC to 2022-11-16 15:07:18 UTC - Fix Install MdBook command (rust-lang/book#3424) ## rust-embedded/book 4 commits in c533348edd69f11a8f4225d633a05d7093fddbf3..19f798d448835a4888e3b3eae7fe69f1d61d8681 2022-11-17 15:08:11 UTC to 2022-11-08 23:27:57 UTC - start/hardware.md: Fix typo (rust-embedded/book#336) - doc: Fix `arm-none-eabi-gdb` installation instruction for Fedora 27 or newer to just use `gdb` (rust-embedded/book#335) - Update singletons.md (rust-embedded/book#334) - Remove incorrect claim HashMap is avail in no_std (rust-embedded/book#333) ## rust-lang/nomicon 2 commits in 05532356e7a4dbea2330aabb77611f5179493bb8..ae406aa5287a9e025abb72343aaceec98458c117 2022-11-21 22:48:20 UTC to 2022-11-15 00:29:20 UTC - Improve chapter about `Vec<T>` (rust-lang/nomicon#381) - Grammar change for 3.4: Limits of Lifetimes (lifetime-mismatch.md) (rust-lang/nomicon#386) ## rust-lang/reference 9 commits in 9f0cc13ffcd27c1fbe1ab766a9491e15ddcf4d19..3ae62681ff236d5528ef7c8c28ba7c6b2ecc6731 2022-12-05 00:51:50 UTC to 2022-11-15 20:43:30 UTC - Document that type parameter `Self` is unsized by default (rust-lang/reference#1285) - replace `crateid` term with `crate_name` (rust-lang/reference#1310) - Document native library modifier `verbatim` (rust-lang/reference#1299) - Update literal suffix docs for rust-lang#102944 (rust-lang/reference#1305) - update aliasing rules section of the reference (rust-lang/reference#1290) - Document RFC 2867: instruction_set attribute (rust-lang/reference#1253) - Fix a minor typo in the "Higher-ranked trait bounds" section (rust-lang/reference#1288) - Disallow newline directly following `//` (rust-lang/reference#1294) - Add an anchor to the "forwarding macro fragments" paragraph (rust-lang/reference#1300) ## rust-lang/rust-by-example 5 commits in 2b15c0abf2bada6e00553814336bc3e2d8399097..a9869b4a3c4cac3bc6099b41f088679e268400b8 2022-11-27 19:03:05 UTC to 2022-11-11 18:54:53 UTC - Migrate from highfive to triagebot (rust-lang/rust-by-example#1647) - Simpler version of the read_lines script. (rust-lang/rust-by-example#1641) - Fix comment in "Formatted print" example code (rust-lang/rust-by-example#1638) - Added a missing backtick in a comment in chapter 15.4. (rust-lang/rust-by-example#1642) - Clarify the confusing closure example rust-lang#1611 (rust-lang/rust-by-example#1643) ## rust-lang/rustc-dev-guide 13 commits in d0dc6c97a6486f68bac782fff135086eae6d77ec..e269950a57fa6fcda356426545fb5aa3691a7ced 2022-12-03 23:09:24 UTC to 2022-11-08 21:35:38 UTC - Remove duplicate paragraph (rust-lang/rustc-dev-guide#1523) - clarify subtree tool policy (rust-lang/rustc-dev-guide#1518) - Typo (rust-lang/rustc-dev-guide#1520) - Link directly to the section on `--keep-stage` (rust-lang/rustc-dev-guide#1515) - do an actual link to detect if it breaks in future (rust-lang/rustc-dev-guide#1517) - Triage some date-check items (rust-lang/rustc-dev-guide#1513) - Update path for `try_mark_green` implementation (rust-lang/rustc-dev-guide#1512) - Fix a broken design docs link about unused substs bug (rust-lang/rustc-dev-guide#1511) - updating-llvm: keep a calm tone (rust-lang/rustc-dev-guide#1449) - date-check: updating-llvm (rust-lang/rustc-dev-guide#1424) - rewrite the section about regions in the trait solver (rust-lang/rustc-dev-guide#1508) - Consistent ordered list indexing (rust-lang/rustc-dev-guide#1509) - Document multiple alternative suggestions on diagnostic structs (rust-lang/rustc-dev-guide#1486)
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Update books ## rust-lang/book 1 commits in 3f64052c048c6def93b94a2b514ee88bba918744..a60f4316ec923a5ac2ed6a2eba6960edb832d855 2022-11-16 15:07:18 UTC to 2022-11-16 15:07:18 UTC - Fix Install MdBook command (rust-lang/book#3424) ## rust-embedded/book 4 commits in c533348edd69f11a8f4225d633a05d7093fddbf3..19f798d448835a4888e3b3eae7fe69f1d61d8681 2022-11-17 15:08:11 UTC to 2022-11-08 23:27:57 UTC - start/hardware.md: Fix typo (rust-embedded/book#336) - doc: Fix `arm-none-eabi-gdb` installation instruction for Fedora 27 or newer to just use `gdb` (rust-embedded/book#335) - Update singletons.md (rust-embedded/book#334) - Remove incorrect claim HashMap is avail in no_std (rust-embedded/book#333) ## rust-lang/nomicon 2 commits in 05532356e7a4dbea2330aabb77611f5179493bb8..ae406aa5287a9e025abb72343aaceec98458c117 2022-11-21 22:48:20 UTC to 2022-11-15 00:29:20 UTC - Improve chapter about `Vec<T>` (rust-lang/nomicon#381) - Grammar change for 3.4: Limits of Lifetimes (lifetime-mismatch.md) (rust-lang/nomicon#386) ## rust-lang/reference 9 commits in 9f0cc13ffcd27c1fbe1ab766a9491e15ddcf4d19..3ae62681ff236d5528ef7c8c28ba7c6b2ecc6731 2022-12-05 00:51:50 UTC to 2022-11-15 20:43:30 UTC - Document that type parameter `Self` is unsized by default (rust-lang/reference#1285) - replace `crateid` term with `crate_name` (rust-lang/reference#1310) - Document native library modifier `verbatim` (rust-lang/reference#1299) - Update literal suffix docs for rust-lang#102944 (rust-lang/reference#1305) - update aliasing rules section of the reference (rust-lang/reference#1290) - Document RFC 2867: instruction_set attribute (rust-lang/reference#1253) - Fix a minor typo in the "Higher-ranked trait bounds" section (rust-lang/reference#1288) - Disallow newline directly following `//` (rust-lang/reference#1294) - Add an anchor to the "forwarding macro fragments" paragraph (rust-lang/reference#1300) ## rust-lang/rust-by-example 5 commits in 2b15c0abf2bada6e00553814336bc3e2d8399097..a9869b4a3c4cac3bc6099b41f088679e268400b8 2022-11-27 19:03:05 UTC to 2022-11-11 18:54:53 UTC - Migrate from highfive to triagebot (rust-lang/rust-by-example#1647) - Simpler version of the read_lines script. (rust-lang/rust-by-example#1641) - Fix comment in "Formatted print" example code (rust-lang/rust-by-example#1638) - Added a missing backtick in a comment in chapter 15.4. (rust-lang/rust-by-example#1642) - Clarify the confusing closure example rust-lang#1611 (rust-lang/rust-by-example#1643) ## rust-lang/rustc-dev-guide 13 commits in d0dc6c97a6486f68bac782fff135086eae6d77ec..e269950a57fa6fcda356426545fb5aa3691a7ced 2022-12-03 23:09:24 UTC to 2022-11-08 21:35:38 UTC - Remove duplicate paragraph (rust-lang/rustc-dev-guide#1523) - clarify subtree tool policy (rust-lang/rustc-dev-guide#1518) - Typo (rust-lang/rustc-dev-guide#1520) - Link directly to the section on `--keep-stage` (rust-lang/rustc-dev-guide#1515) - do an actual link to detect if it breaks in future (rust-lang/rustc-dev-guide#1517) - Triage some date-check items (rust-lang/rustc-dev-guide#1513) - Update path for `try_mark_green` implementation (rust-lang/rustc-dev-guide#1512) - Fix a broken design docs link about unused substs bug (rust-lang/rustc-dev-guide#1511) - updating-llvm: keep a calm tone (rust-lang/rustc-dev-guide#1449) - date-check: updating-llvm (rust-lang/rustc-dev-guide#1424) - rewrite the section about regions in the trait solver (rust-lang/rustc-dev-guide#1508) - Consistent ordered list indexing (rust-lang/rustc-dev-guide#1509) - Document multiple alternative suggestions on diagnostic structs (rust-lang/rustc-dev-guide#1486)
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Update books ## rust-lang/book 1 commits in 3f64052c048c6def93b94a2b514ee88bba918744..a60f4316ec923a5ac2ed6a2eba6960edb832d855 2022-11-16 15:07:18 UTC to 2022-11-16 15:07:18 UTC - Fix Install MdBook command (rust-lang/book#3424) ## rust-embedded/book 4 commits in c533348edd69f11a8f4225d633a05d7093fddbf3..19f798d448835a4888e3b3eae7fe69f1d61d8681 2022-11-17 15:08:11 UTC to 2022-11-08 23:27:57 UTC - start/hardware.md: Fix typo (rust-embedded/book#336) - doc: Fix `arm-none-eabi-gdb` installation instruction for Fedora 27 or newer to just use `gdb` (rust-embedded/book#335) - Update singletons.md (rust-embedded/book#334) - Remove incorrect claim HashMap is avail in no_std (rust-embedded/book#333) ## rust-lang/nomicon 2 commits in 05532356e7a4dbea2330aabb77611f5179493bb8..ae406aa5287a9e025abb72343aaceec98458c117 2022-11-21 22:48:20 UTC to 2022-11-15 00:29:20 UTC - Improve chapter about `Vec<T>` (rust-lang/nomicon#381) - Grammar change for 3.4: Limits of Lifetimes (lifetime-mismatch.md) (rust-lang/nomicon#386) ## rust-lang/reference 9 commits in 9f0cc13ffcd27c1fbe1ab766a9491e15ddcf4d19..3ae62681ff236d5528ef7c8c28ba7c6b2ecc6731 2022-12-05 00:51:50 UTC to 2022-11-15 20:43:30 UTC - Document that type parameter `Self` is unsized by default (rust-lang/reference#1285) - replace `crateid` term with `crate_name` (rust-lang/reference#1310) - Document native library modifier `verbatim` (rust-lang/reference#1299) - Update literal suffix docs for rust-lang#102944 (rust-lang/reference#1305) - update aliasing rules section of the reference (rust-lang/reference#1290) - Document RFC 2867: instruction_set attribute (rust-lang/reference#1253) - Fix a minor typo in the "Higher-ranked trait bounds" section (rust-lang/reference#1288) - Disallow newline directly following `//` (rust-lang/reference#1294) - Add an anchor to the "forwarding macro fragments" paragraph (rust-lang/reference#1300) ## rust-lang/rust-by-example 5 commits in 2b15c0abf2bada6e00553814336bc3e2d8399097..a9869b4a3c4cac3bc6099b41f088679e268400b8 2022-11-27 19:03:05 UTC to 2022-11-11 18:54:53 UTC - Migrate from highfive to triagebot (rust-lang/rust-by-example#1647) - Simpler version of the read_lines script. (rust-lang/rust-by-example#1641) - Fix comment in "Formatted print" example code (rust-lang/rust-by-example#1638) - Added a missing backtick in a comment in chapter 15.4. (rust-lang/rust-by-example#1642) - Clarify the confusing closure example rust-lang#1611 (rust-lang/rust-by-example#1643) ## rust-lang/rustc-dev-guide 13 commits in d0dc6c97a6486f68bac782fff135086eae6d77ec..e269950a57fa6fcda356426545fb5aa3691a7ced 2022-12-03 23:09:24 UTC to 2022-11-08 21:35:38 UTC - Remove duplicate paragraph (rust-lang/rustc-dev-guide#1523) - clarify subtree tool policy (rust-lang/rustc-dev-guide#1518) - Typo (rust-lang/rustc-dev-guide#1520) - Link directly to the section on `--keep-stage` (rust-lang/rustc-dev-guide#1515) - do an actual link to detect if it breaks in future (rust-lang/rustc-dev-guide#1517) - Triage some date-check items (rust-lang/rustc-dev-guide#1513) - Update path for `try_mark_green` implementation (rust-lang/rustc-dev-guide#1512) - Fix a broken design docs link about unused substs bug (rust-lang/rustc-dev-guide#1511) - updating-llvm: keep a calm tone (rust-lang/rustc-dev-guide#1449) - date-check: updating-llvm (rust-lang/rustc-dev-guide#1424) - rewrite the section about regions in the trait solver (rust-lang/rustc-dev-guide#1508) - Consistent ordered list indexing (rust-lang/rustc-dev-guide#1509) - Document multiple alternative suggestions on diagnostic structs (rust-lang/rustc-dev-guide#1486)
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Stop mentioning
PhantomData<T>and dropck in the vec chapter except at the start for linking to the phantom-data chapter, and a few style improvements. See the commits for more details.