documentation for fmt binary trait: slightly misleading example #116165
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…oshtriplett Correct misleading std::fmt::Binary example (rust-lang#116165) Nothing too crazy... - Add two to the width specifier (so all 32 bits are correctly displayed) - Pad out the compared string so the assert passes - Add `// Note` comment highlighting the need for the extra width when using the `#` flag. The exact contents (and placement?) of the note are, of course, highly bikesheddable.
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…iaskrgr Rollup of 3 pull requests Successful merges: - rust-lang#116313 (Some small cleanups in `rustc_abi`) - rust-lang#116326 (Correct misleading std::fmt::Binary example (rust-lang#116165)) - rust-lang#116340 (`skip_binder` to `instantiate_identity`) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup merge of rust-lang#116326 - Colonial-Dev:issue-116165-fix, r=joshtriplett Correct misleading std::fmt::Binary example (rust-lang#116165) Nothing too crazy... - Add two to the width specifier (so all 32 bits are correctly displayed) - Pad out the compared string so the assert passes - Add `// Note` comment highlighting the need for the extra width when using the `#` flag. The exact contents (and placement?) of the note are, of course, highly bikesheddable.
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Hmm, you'd think Bors would have closed this automatically... |
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In the PR description you need to write something like "fixes #116165" so that github will know they're associated. See Linking a pull request to an issue. |
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Location
https://doc.rust-lang.org/std/fmt/trait.Binary.html
Specifically the last assert in the Examples section:
assert_eq!( format!("l as binary is: {l:#032b}"), "l as binary is: 0b000000000000000000000001101011" );Summary
This example shows how to format the binary representation of an i32 and was probably meant to display all 32 bits, but actually only displays 30 bits because the alternate flag
#adds the prefix0bto the representation, which is included in the total width of the padding (which is mentioned in passing here: https://doc.rust-lang.org/std/fmt/index.html#sign0 ).I think it would be useful to mention in that example that the
0bprefix is included in the total width, and I would also suggest changing the example to use{l:#034b}as that is probably what the reader is expecting when displaying a padded i32,The text was updated successfully, but these errors were encountered: