Document convention for using both fmt::Write and io::Write #37472

joshtriplett · 2016-10-29T22:34:57Z

Using a trait's methods (like Write::write_fmt as used in writeln! and other macros) requires importing that trait directly (not just the module containing it). Both fmt::Write and io::Write provide compatible Write::write_fmt methods, and code can use writeln! and other macros on both an object implementing fmt::Write (such as a String) and an object implementing io::Write (such as Stderr). However, importing both Write traits produces an error due to the name conflict.

The convention I've seen renames both of them on import, to FmtWrite and IoWrite respectively. Document that convention in the Rust documentation for write! and writeln!, with examples.

…fmt::Write Various existing code does this, but the documentation doesn't explain how to do it.

rust-highfive · 2016-10-29T22:35:10Z

Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @brson (or someone else) soon.

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…teln, r=alexcrichton Copyediting on documentation for write! and writeln! Fix various sentence fragments, missing articles, and other grammatical issues in the documentation for write! and writeln!. Also fix the links (and link names) for common return types. (Noticed when preparing rust-lang#37472 ; posted separately to avoid mixing the new documentation with copyedits to existing documentation.)

brson · 2016-11-09T02:48:54Z

@bors r+ rollup

bors · 2016-11-09T02:48:55Z

📌 Commit 955829c has been approved by brson

…, r=brson Document convention for using both fmt::Write and io::Write Using a trait's methods (like `Write::write_fmt` as used in `writeln!` and other macros) requires importing that trait directly (not just the module containing it). Both `fmt::Write` and `io::Write` provide compatible `Write::write_fmt` methods, and code can use `writeln!` and other macros on both an object implementing `fmt::Write` (such as a `String`) and an object implementing `io::Write` (such as `Stderr`). However, importing both `Write` traits produces an error due to the name conflict. The convention I've seen renames both of them on import, to `FmtWrite` and `IoWrite` respectively. Document that convention in the Rust documentation for `write!` and `writeln!`, with examples.

Rollup of 15 pull requests - Successful merges: #36868, #37134, #37229, #37250, #37370, #37428, #37432, #37472, #37524, #37614, #37622, #37627, #37636, #37644, #37654 - Failed merges: #37463, #37542, #37645

…mulacrum Update documentation for `write!` and `writeln!` rust-lang#37472 added this documentation, but it needs updating: - Remove some documentation duplicated between `writeln!` and `write!` - Update `write!` docs: can now import traits as `_` to avoid conflicts - Expand example to show how to implement qualified trait names

Update documentation for `write!` and `writeln!` rust-lang/rust#37472 added this documentation, but it needs updating: - Remove some documentation duplicated between `writeln!` and `write!` - Update `write!` docs: can now import traits as `_` to avoid conflicts - Expand example to show how to implement qualified trait names

Add documentation to write! and writeln! on using both io::Write and …

955829c

…fmt::Write Various existing code does this, but the documentation doesn't explain how to do it.

rust-highfive assigned brson Oct 29, 2016

joshtriplett mentioned this pull request Oct 29, 2016

Copyediting on documentation for write! and writeln! #37473

Merged

eddyb mentioned this pull request Nov 9, 2016

Rollup of 15 pull requests #37670

Merged

bors merged commit 955829c into rust-lang:master Nov 9, 2016

joshtriplett deleted the doc-fmt-write-io-write branch July 26, 2017 23:31

joshtriplett mentioned this pull request Aug 24, 2022

Update documentation for write! and writeln! #100953

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Document convention for using both fmt::Write and io::Write #37472

Document convention for using both fmt::Write and io::Write #37472

joshtriplett commented Oct 29, 2016

rust-highfive commented Oct 29, 2016

brson commented Nov 9, 2016

bors commented Nov 9, 2016

Document convention for using both fmt::Write and io::Write #37472

Document convention for using both fmt::Write and io::Write #37472

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joshtriplett commented Oct 29, 2016

rust-highfive commented Oct 29, 2016

brson commented Nov 9, 2016

bors commented Nov 9, 2016