Mark std::fmt::from_fn as #[must_use]
#136502
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I think this is fine but it should get an ack from the api team r? libs-api
This should be simple enough to figure out now, maybe something along the lines of "result does nothing unless used in a formatter". |
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"returns a type implementing Debug and Display, which do not have any effects unless they are used". |
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I think burntsushi has been taking a break from reviews r? libs-api |
Maybe "in a formatting operation"? |
I like that one.. |
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The need to avoid "formatter" or "formatting operation" becomes obvious considering you could just call |
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@bors r+ rollup |
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… r=dtolnay Mark `std::fmt::from_fn` as `#[must_use]` While working on rust-lang#135494 I managed to shoot my own foot a few times by forgetting to actually use the result of `fmt::from_fn`, so I think a `#[must_use]` could be appropriate! Didn't have a good message to put in the attr so left it blank, still unstable so we can come back to it I guess? cc rust-lang#117729 (and a huge +1 for getting it stabilized, it's very useful IMHO)
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Rollup of 9 pull requests Successful merges: - rust-lang#128045 (#[contracts::requires(...)] + #[contracts::ensures(...)]) - rust-lang#136263 (rustdoc: clean up a bunch of ts-expected-error declarations in main) - rust-lang#136375 (cg_llvm: Replace some DIBuilder wrappers with LLVM-C API bindings (part 1)) - rust-lang#136392 (bootstrap: add wrapper macros for `feature = "tracing"`-gated `tracing` macros) - rust-lang#136405 (rustdoc-book: Clean up section on `--output-format`) - rust-lang#136497 (Report generic mismatches when calling bodyless trait functions) - rust-lang#136502 (Mark `std::fmt::from_fn` as `#[must_use]`) - rust-lang#136509 (Add tests for nested macro_rules edition behavior) - rust-lang#136526 (mir_build: Rename `thir::cx::Cx` to `ThirBuildCx` and remove `UserAnnotatedTyHelpers`) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup of 8 pull requests Successful merges: - rust-lang#128045 (#[contracts::requires(...)] + #[contracts::ensures(...)]) - rust-lang#136263 (rustdoc: clean up a bunch of ts-expected-error declarations in main) - rust-lang#136375 (cg_llvm: Replace some DIBuilder wrappers with LLVM-C API bindings (part 1)) - rust-lang#136392 (bootstrap: add wrapper macros for `feature = "tracing"`-gated `tracing` macros) - rust-lang#136396 (rustdoc-json-types: Document that crate name isn't package name.) - rust-lang#136405 (rustdoc-book: Clean up section on `--output-format`) - rust-lang#136502 (Mark `std::fmt::from_fn` as `#[must_use]`) - rust-lang#136509 (Add tests for nested macro_rules edition behavior) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup merge of rust-lang#136502 - yotamofek:pr/fmt-from-fn-must-use, r=dtolnay Mark `std::fmt::from_fn` as `#[must_use]` While working on rust-lang#135494 I managed to shoot my own foot a few times by forgetting to actually use the result of `fmt::from_fn`, so I think a `#[must_use]` could be appropriate! Didn't have a good message to put in the attr so left it blank, still unstable so we can come back to it I guess? cc rust-lang#117729 (and a huge +1 for getting it stabilized, it's very useful IMHO)
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While working on #135494 I managed to shoot my own foot a few times by forgetting to actually use the result of
fmt::from_fn, so I think a#[must_use]could be appropriate!Didn't have a good message to put in the attr so left it blank, still unstable so we can come back to it I guess?
cc #117729 (and a huge +1 for getting it stabilized, it's very useful IMHO)