Match Ergonomics 2024: add context and examples to the unstable book #137358

dianne · 2025-02-21T02:24:25Z

The examples here are pretty limited and don't illustrate the differences between the two feature gates, but my hope is that they get the general idea across. I can try and add some more nuance or more comprehensive examples too if that would help.

Hopefully the doctest isn't too sneaky. I wanted to make the bindings' types explicit, and the most readable way I could think of was to use a helper.

Unfortunately it looks like the "run this code" button doesn't work yet, but I made sure the examples are cross-edition, so that should resolve on its own once playground's nightly updates (or if playground's default becomes edition 2024, or if the edition in the markdown gets forwarded to playground). It looks like the default edition on playground is now 2024, so the run button works! There's no output, but having a button to show that it compiles is nice, I think.

Relevant tracking issue: #123076

r? @Nadrieril

…book

Nadrieril · 2025-03-05T10:43:16Z

Looks good, that's already a lot more helpful for someone stumbling upon these feature gates. Thanks!

@bors r+ rollup

bors · 2025-03-05T10:43:19Z

📌 Commit 812b1de has been approved by Nadrieril

It is now in the queue for this repository.

…es, r=Nadrieril Match Ergonomics 2024: add context and examples to the unstable book The examples here are pretty limited and don't illustrate the differences between the two feature gates, but my hope is that they get the general idea across. I can try and add some more nuance or more comprehensive examples too if that would help. Hopefully the doctest isn't too sneaky. I wanted to make the bindings' types explicit, and the most readable way I could think of was to use a helper. ~~Unfortunately it looks like the "run this code" button doesn't work yet, but I made sure the examples are cross-edition, so that should resolve on its own once playground's nightly updates (or if playground's default becomes edition 2024, or if the edition in the markdown gets forwarded to playground).~~ It looks like the default edition on playground is now 2024, so the run button works! There's no output, but having a button to show that it compiles is nice, I think. Relevant tracking issue: rust-lang#123076 r? `@Nadrieril`

Rollup of 23 pull requests Successful merges: - rust-lang#137303 (Remove `MaybeForgetReturn` suggestion) - rust-lang#137327 (Undeprecate env::home_dir) - rust-lang#137358 (Match Ergonomics 2024: add context and examples to the unstable book) - rust-lang#137534 ([rustdoc] hide item that is not marked as doc(inline) and whose src is doc(hidden)) - rust-lang#137565 (Try to point of macro expansion from resolver and method errors if it involves macro var) - rust-lang#137637 (Check dyn flavor before registering upcast goal on wide pointer cast in MIR typeck) - rust-lang#137643 (Add DWARF test case for non-C-like `repr128` enums) - rust-lang#137744 (Re-add `Clone`-derive on `Thir`) - rust-lang#137758 (fix usage of ty decl macro fragments in attributes) - rust-lang#137764 (Ensure that negative auto impls are always applicable) - rust-lang#137772 (Fix char count in `Display` for `ByteStr`) - rust-lang#137798 (ci: use ubuntu 24 on arm large runner) - rust-lang#137802 (miri native-call support: all previously exposed provenance is accessible to the callee) - rust-lang#137805 (adjust Layout debug printing to match the internal field name) - rust-lang#137808 (Do not require that unsafe fields lack drop glue) - rust-lang#137820 (Clarify why InhabitedPredicate::instantiate_opt exists) - rust-lang#137825 (Provide more context on resolve error caused from incorrect RTN) - rust-lang#137910 (Improve error message for `AsyncFn` trait failure for RPIT) - rust-lang#137920 (interpret/provenance_map: consistently use range_is_empty) - rust-lang#138038 (Update `compiler-builtins` to 0.1.151) - rust-lang#138041 (bootstrap and compiletest: Use `size_of_val` from the prelude instead of imported) - rust-lang#138046 (trim channel value in `get_closest_merge_commit`) - rust-lang#138053 (Increase the max. custom try jobs requested to `20`) r? `@ghost` `@rustbot` modify labels: rollup

…es, r=Nadrieril Match Ergonomics 2024: add context and examples to the unstable book The examples here are pretty limited and don't illustrate the differences between the two feature gates, but my hope is that they get the general idea across. I can try and add some more nuance or more comprehensive examples too if that would help. Hopefully the doctest isn't too sneaky. I wanted to make the bindings' types explicit, and the most readable way I could think of was to use a helper. ~~Unfortunately it looks like the "run this code" button doesn't work yet, but I made sure the examples are cross-edition, so that should resolve on its own once playground's nightly updates (or if playground's default becomes edition 2024, or if the edition in the markdown gets forwarded to playground).~~ It looks like the default edition on playground is now 2024, so the run button works! There's no output, but having a button to show that it compiles is nice, I think. Relevant tracking issue: rust-lang#123076 r? ``@Nadrieril``

Rollup of 29 pull requests Successful merges: - rust-lang#135733 (Implement `&pin const self` and `&pin mut self` sugars) - rust-lang#137107 (Override default `Write` methods for cursor-like types) - rust-lang#137303 (Remove `MaybeForgetReturn` suggestion) - rust-lang#137327 (Undeprecate env::home_dir) - rust-lang#137358 (Match Ergonomics 2024: add context and examples to the unstable book) - rust-lang#137534 ([rustdoc] hide item that is not marked as doc(inline) and whose src is doc(hidden)) - rust-lang#137565 (Try to point of macro expansion from resolver and method errors if it involves macro var) - rust-lang#137612 (Update bootstrap to edition 2024) - rust-lang#137637 (Check dyn flavor before registering upcast goal on wide pointer cast in MIR typeck) - rust-lang#137643 (Add DWARF test case for non-C-like `repr128` enums) - rust-lang#137685 (self-contained linker: conservatively default to `-znostart-stop-gc` on x64 linux) - rust-lang#137744 (Re-add `Clone`-derive on `Thir`) - rust-lang#137758 (fix usage of ty decl macro fragments in attributes) - rust-lang#137764 (Ensure that negative auto impls are always applicable) - rust-lang#137772 (Fix char count in `Display` for `ByteStr`) - rust-lang#137798 (ci: use ubuntu 24 on arm large runner) - rust-lang#137802 (miri native-call support: all previously exposed provenance is accessible to the callee) - rust-lang#137805 (adjust Layout debug printing to match the internal field name) - rust-lang#137808 (Do not require that unsafe fields lack drop glue) - rust-lang#137820 (Clarify why InhabitedPredicate::instantiate_opt exists) - rust-lang#137825 (Provide more context on resolve error caused from incorrect RTN) - rust-lang#137827 (Add timestamp to unstable feature usage metrics) - rust-lang#137832 (Fix crash in BufReader::peek()) - rust-lang#137910 (Improve error message for `AsyncFn` trait failure for RPIT) - rust-lang#137920 (interpret/provenance_map: consistently use range_is_empty) - rust-lang#138038 (Update `compiler-builtins` to 0.1.151) - rust-lang#138046 (trim channel value in `get_closest_merge_commit`) - rust-lang#138052 (strip `-Wlinker-messages` wrappers from `rust-lld` rmake test) - rust-lang#138053 (Increase the max. custom try jobs requested to `20`) r? `@ghost` `@rustbot` modify labels: rollup

…es, r=Nadrieril Match Ergonomics 2024: add context and examples to the unstable book The examples here are pretty limited and don't illustrate the differences between the two feature gates, but my hope is that they get the general idea across. I can try and add some more nuance or more comprehensive examples too if that would help. Hopefully the doctest isn't too sneaky. I wanted to make the bindings' types explicit, and the most readable way I could think of was to use a helper. ~~Unfortunately it looks like the "run this code" button doesn't work yet, but I made sure the examples are cross-edition, so that should resolve on its own once playground's nightly updates (or if playground's default becomes edition 2024, or if the edition in the markdown gets forwarded to playground).~~ It looks like the default edition on playground is now 2024, so the run button works! There's no output, but having a button to show that it compiles is nice, I think. Relevant tracking issue: rust-lang#123076 r? ```@Nadrieril```

…es, r=Nadrieril Match Ergonomics 2024: add context and examples to the unstable book The examples here are pretty limited and don't illustrate the differences between the two feature gates, but my hope is that they get the general idea across. I can try and add some more nuance or more comprehensive examples too if that would help. Hopefully the doctest isn't too sneaky. I wanted to make the bindings' types explicit, and the most readable way I could think of was to use a helper. ~~Unfortunately it looks like the "run this code" button doesn't work yet, but I made sure the examples are cross-edition, so that should resolve on its own once playground's nightly updates (or if playground's default becomes edition 2024, or if the edition in the markdown gets forwarded to playground).~~ It looks like the default edition on playground is now 2024, so the run button works! There's no output, but having a button to show that it compiles is nice, I think. Relevant tracking issue: rust-lang#123076 r? ````@Nadrieril````

…es, r=Nadrieril Match Ergonomics 2024: add context and examples to the unstable book The examples here are pretty limited and don't illustrate the differences between the two feature gates, but my hope is that they get the general idea across. I can try and add some more nuance or more comprehensive examples too if that would help. Hopefully the doctest isn't too sneaky. I wanted to make the bindings' types explicit, and the most readable way I could think of was to use a helper. ~~Unfortunately it looks like the "run this code" button doesn't work yet, but I made sure the examples are cross-edition, so that should resolve on its own once playground's nightly updates (or if playground's default becomes edition 2024, or if the edition in the markdown gets forwarded to playground).~~ It looks like the default edition on playground is now 2024, so the run button works! There's no output, but having a button to show that it compiles is nice, I think. Relevant tracking issue: rust-lang#123076 r? `````@Nadrieril`````

…compiler-errors Rollup of 20 pull requests Successful merges: - rust-lang#137303 (Remove `MaybeForgetReturn` suggestion) - rust-lang#137327 (Undeprecate env::home_dir) - rust-lang#137358 (Match Ergonomics 2024: add context and examples to the unstable book) - rust-lang#137502 (Don't include global asm in `mir_keys`, fix error body synthesis) - rust-lang#137534 ([rustdoc] hide item that is not marked as doc(inline) and whose src is doc(hidden)) - rust-lang#137565 (Try to point of macro expansion from resolver and method errors if it involves macro var) - rust-lang#137637 (Check dyn flavor before registering upcast goal on wide pointer cast in MIR typeck) - rust-lang#137643 (Add DWARF test case for non-C-like `repr128` enums) - rust-lang#137744 (Re-add `Clone`-derive on `Thir`) - rust-lang#137758 (fix usage of ty decl macro fragments in attributes) - rust-lang#137764 (Ensure that negative auto impls are always applicable) - rust-lang#137772 (Fix char count in `Display` for `ByteStr`) - rust-lang#137798 (ci: use ubuntu 24 on arm large runner) - rust-lang#137802 (miri native-call support: all previously exposed provenance is accessible to the callee) - rust-lang#137805 (adjust Layout debug printing to match the internal field name) - rust-lang#137808 (Do not require that unsafe fields lack drop glue) - rust-lang#137820 (Clarify why InhabitedPredicate::instantiate_opt exists) - rust-lang#137825 (Provide more context on resolve error caused from incorrect RTN) - rust-lang#137868 (Add minimal platform support documentation for powerpc-unknown-linux-gnuspe) - rust-lang#137910 (Improve error message for `AsyncFn` trait failure for RPIT) r? `@ghost` `@rustbot` modify labels: rollup

…mpiler-errors Rollup of 20 pull requests Successful merges: - rust-lang#137303 (Remove `MaybeForgetReturn` suggestion) - rust-lang#137327 (Undeprecate env::home_dir) - rust-lang#137358 (Match Ergonomics 2024: add context and examples to the unstable book) - rust-lang#137502 (Don't include global asm in `mir_keys`, fix error body synthesis) - rust-lang#137534 ([rustdoc] hide item that is not marked as doc(inline) and whose src is doc(hidden)) - rust-lang#137565 (Try to point of macro expansion from resolver and method errors if it involves macro var) - rust-lang#137637 (Check dyn flavor before registering upcast goal on wide pointer cast in MIR typeck) - rust-lang#137643 (Add DWARF test case for non-C-like `repr128` enums) - rust-lang#137744 (Re-add `Clone`-derive on `Thir`) - rust-lang#137758 (fix usage of ty decl macro fragments in attributes) - rust-lang#137764 (Ensure that negative auto impls are always applicable) - rust-lang#137772 (Fix char count in `Display` for `ByteStr`) - rust-lang#137798 (ci: use ubuntu 24 on arm large runner) - rust-lang#137802 (miri native-call support: all previously exposed provenance is accessible to the callee) - rust-lang#137805 (adjust Layout debug printing to match the internal field name) - rust-lang#137808 (Do not require that unsafe fields lack drop glue) - rust-lang#137820 (Clarify why InhabitedPredicate::instantiate_opt exists) - rust-lang#137825 (Provide more context on resolve error caused from incorrect RTN) - rust-lang#137868 (Add minimal platform support documentation for powerpc-unknown-linux-gnuspe) - rust-lang#137910 (Improve error message for `AsyncFn` trait failure for RPIT) r? `@ghost` `@rustbot` modify labels: rollup

…mpiler-errors Rollup of 25 pull requests Successful merges: - rust-lang#135733 (Implement `&pin const self` and `&pin mut self` sugars) - rust-lang#135895 (Document workings of successors more clearly) - rust-lang#136922 (Pattern types: Avoid having to handle an Option for range ends in the type system or the HIR) - rust-lang#137303 (Remove `MaybeForgetReturn` suggestion) - rust-lang#137327 (Undeprecate env::home_dir) - rust-lang#137358 (Match Ergonomics 2024: add context and examples to the unstable book) - rust-lang#137534 ([rustdoc] hide item that is not marked as doc(inline) and whose src is doc(hidden)) - rust-lang#137565 (Try to point of macro expansion from resolver and method errors if it involves macro var) - rust-lang#137637 (Check dyn flavor before registering upcast goal on wide pointer cast in MIR typeck) - rust-lang#137643 (Add DWARF test case for non-C-like `repr128` enums) - rust-lang#137744 (Re-add `Clone`-derive on `Thir`) - rust-lang#137758 (fix usage of ty decl macro fragments in attributes) - rust-lang#137764 (Ensure that negative auto impls are always applicable) - rust-lang#137772 (Fix char count in `Display` for `ByteStr`) - rust-lang#137798 (ci: use ubuntu 24 on arm large runner) - rust-lang#137802 (miri native-call support: all previously exposed provenance is accessible to the callee) - rust-lang#137805 (adjust Layout debug printing to match the internal field name) - rust-lang#137808 (Do not require that unsafe fields lack drop glue) - rust-lang#137820 (Clarify why InhabitedPredicate::instantiate_opt exists) - rust-lang#137825 (Provide more context on resolve error caused from incorrect RTN) - rust-lang#137834 (rustc_fluent_macro: use CARGO_CRATE_NAME instead of CARGO_PKG_NAME) - rust-lang#137868 (Add minimal platform support documentation for powerpc-unknown-linux-gnuspe) - rust-lang#137910 (Improve error message for `AsyncFn` trait failure for RPIT) - rust-lang#137920 (interpret/provenance_map: consistently use range_is_empty) - rust-lang#138038 (Update `compiler-builtins` to 0.1.151) r? `@ghost` `@rustbot` modify labels: rollup

Rollup merge of rust-lang#137358 - dianne:new-match-ergonomics-examples, r=Nadrieril Match Ergonomics 2024: add context and examples to the unstable book The examples here are pretty limited and don't illustrate the differences between the two feature gates, but my hope is that they get the general idea across. I can try and add some more nuance or more comprehensive examples too if that would help. Hopefully the doctest isn't too sneaky. I wanted to make the bindings' types explicit, and the most readable way I could think of was to use a helper. ~~Unfortunately it looks like the "run this code" button doesn't work yet, but I made sure the examples are cross-edition, so that should resolve on its own once playground's nightly updates (or if playground's default becomes edition 2024, or if the edition in the markdown gets forwarded to playground).~~ It looks like the default edition on playground is now 2024, so the run button works! There's no output, but having a button to show that it compiles is nice, I think. Relevant tracking issue: rust-lang#123076 r? ``````@Nadrieril``````

ref_pat_eat_one_layer_2024: add context and examples to the unstable …

812b1de

…book

rustbot assigned Nadrieril Feb 21, 2025

rustbot added the S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. label Feb 21, 2025

bors added S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels Mar 5, 2025

jieyouxu mentioned this pull request Mar 5, 2025

Rollup of 23 pull requests #138059

Closed

jieyouxu mentioned this pull request Mar 5, 2025

Rollup of 29 pull requests #138071

Closed

jieyouxu mentioned this pull request Mar 5, 2025

Rollup of 15 pull requests #138072

Closed

compiler-errors mentioned this pull request Mar 6, 2025

Rollup of 20 pull requests #138079

Closed

Noratrieb mentioned this pull request Mar 6, 2025

Rollup of 42 pull requests #138086

Closed

compiler-errors mentioned this pull request Mar 6, 2025

Rollup of 25 pull requests #138114

Merged

bors merged commit 98dfe93 into rust-lang:master Mar 7, 2025
6 checks passed

rustbot added this to the 1.87.0 milestone Mar 7, 2025

dianne deleted the new-match-ergonomics-examples branch March 7, 2025 09:24

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Match Ergonomics 2024: add context and examples to the unstable book #137358

Match Ergonomics 2024: add context and examples to the unstable book #137358

dianne commented Feb 21, 2025 •

edited

Loading

Nadrieril commented Mar 5, 2025 •

edited

Loading

bors commented Mar 5, 2025

Match Ergonomics 2024: add context and examples to the unstable book #137358

Match Ergonomics 2024: add context and examples to the unstable book #137358

Conversation

dianne commented Feb 21, 2025 • edited Loading

Nadrieril commented Mar 5, 2025 • edited Loading

bors commented Mar 5, 2025

dianne commented Feb 21, 2025 •

edited

Loading

Nadrieril commented Mar 5, 2025 •

edited

Loading