diff options
author | Robin Krahl <robin.krahl@ireas.org> | 2020-01-07 11:18:04 +0000 |
---|---|---|
committer | Daniel Mueller <deso@posteo.net> | 2020-01-08 09:20:25 -0800 |
commit | 5e20a29b4fdc8a2d442d1093681b396dcb4b816b (patch) | |
tree | 55ab083fa8999d2ccbb5e921c1ffe52560dca152 /rustversion/README.md | |
parent | 203e691f46d591a2cc8acdfd850fa9f5b0fb8a98 (diff) | |
download | nitrocli-5e20a29b4fdc8a2d442d1093681b396dcb4b816b.tar.gz nitrocli-5e20a29b4fdc8a2d442d1093681b396dcb4b816b.tar.bz2 |
Add structopt dependency in version 0.3.7
This patch series replaces argparse with structopt in the argument
handling code. As a first step, we need structopt as a dependency.
Import subrepo structopt/:structopt at efbdda4753592e27bc430fb01f7b9650b2f3174d
Import subrepo bitflags/:bitflags at 30668016aca6bd3b02c766e8347e0b4080d4c296
Import subrepo clap/:clap at 784524f7eb193e35f81082cc69454c8c21b948f7
Import subrepo heck/:heck at 093d56fbf001e1506e56dbfa38631d99b1066df1
Import subrepo proc-macro-error/:proc-macro-error at 6c4cfe79a622c5de8ae68557993542be46eacae2
Import subrepo proc-macro2/:proc-macro2 at d5d48eddca4566e5438e8a2cbed4a74e049544de
Import subrepo quote/:quote at 727436c6c137b20f0f34dde5d8fda2679b9747ad
Import subrepo rustversion/:rustversion at 0c5663313516263059ce9059ef81fc7a1cf655ca
Import subrepo syn-mid/:syn-mid at 5d3d85414a9e6674e1857ec22a87b96e04a6851a
Import subrepo syn/:syn at e87c27e87f6f4ef8919d0372bdb056d53ef0d8f3
Import subrepo textwrap/:textwrap at abcd618beae3f74841032aa5b53c1086b0a57ca2
Import subrepo unicode-segmentation/:unicode-segmentation at 637c9874c4fe0c205ff27787faf150a40295c6c3
Import subrepo unicode-width/:unicode-width at 3033826f8bf05e82724140a981d5941e48fce393
Import subrepo unicode-xid/:unicode-xid at 4baae9fffb156ba229665b972a9cd5991787ceb7
Diffstat (limited to 'rustversion/README.md')
-rw-r--r-- | rustversion/README.md | 138 |
1 files changed, 138 insertions, 0 deletions
diff --git a/rustversion/README.md b/rustversion/README.md new file mode 100644 index 0000000..f7fdab1 --- /dev/null +++ b/rustversion/README.md @@ -0,0 +1,138 @@ +Compiler version cfg +==================== + +[![Build Status](https://api.travis-ci.com/dtolnay/rustversion.svg?branch=master)](https://travis-ci.com/dtolnay/rustversion) +[![Latest Version](https://img.shields.io/crates/v/rustversion.svg)](https://crates.io/crates/rustversion) +[![Rust Documentation](https://img.shields.io/badge/api-rustdoc-blue.svg)](https://docs.rs/rustversion) + +This crate provides macros for conditional compilation according to rustc +compiler version, analogous to [`#[cfg(...)]`][cfg] and +[`#[cfg_attr(...)]`][cfg_attr]. + +[cfg]: https://doc.rust-lang.org/reference/conditional-compilation.html#the-cfg-attribute +[cfg_attr]: https://doc.rust-lang.org/reference/conditional-compilation.html#the-cfg_attr-attribute + +```toml +[dependencies] +rustversion = "1.0" +``` + +<br> + +## Selectors + +- <b>`#[rustversion::stable]`</b> + —<br> + True on any stable compiler. + +- <b>`#[rustversion::stable(1.34)]`</b> + —<br> + True on exactly the specified stable compiler. + +- <b>`#[rustversion::beta]`</b> + —<br> + True on any beta compiler. + +- <b>`#[rustversion::nightly]`</b> + —<br> + True on any nightly compiler or dev build. + +- <b>`#[rustversion::nightly(2019-01-01)]`</b> + —<br> + True on exactly one nightly. + +- <b>`#[rustversion::since(1.34)]`</b> + —<br> + True on that stable release and any later compiler, including beta and + nightly. + +- <b>`#[rustversion::since(2019-01-01)]`</b> + —<br> + True on that nightly and all newer ones. + +- <b>`#[rustversion::before(`</b><i>version or date</i><b>`)]`</b> + —<br> + Negative of *#[rustversion::since(...)]*. + +- <b>`#[rustversion::not(`</b><i>selector</i><b>`)]`</b> + —<br> + Negative of any selector; for example *#[rustversion::not(nightly)]*. + +- <b>`#[rustversion::any(`</b><i>selectors...</i><b>`)]`</b> + —<br> + True if any of the comma-separated selectors is true; for example + *#[rustversion::any(stable, beta)]*. + +- <b>`#[rustversion::all(`</b><i>selectors...</i><b>`)]`</b> + —<br> + True if all of the comma-separated selectors are true; for example + *#[rustversion::all(since(1.31), before(1.34))]*. + +- <b>`#[rustversion::attr(`</b><i>selector</i><b>`, `</b><i>attribute</i><b>`)]`</b> + —<br> + For conditional inclusion of attributes; analogous to `cfg_attr`. + +<br> + +## Use cases + +Providing additional trait impls as types are stabilized in the standard library +without breaking compatibility with older compilers; in this case Pin\<P\> +stabilized in [Rust 1.33][pin]: + +[pin]: https://blog.rust-lang.org/2019/02/28/Rust-1.33.0.html#pinning + +```rust +#[rustversion::since(1.33)] +use std::pin::Pin; + +#[rustversion::since(1.33)] +impl<P: MyTrait> MyTrait for Pin<P> { + /* ... */ +} +``` + +Similar but for language features; the ability to control alignment greater than +1 of packed structs was stabilized in [Rust 1.33][packed]. + +[packed]: https://github.com/rust-lang/rust/blob/master/RELEASES.md#version-1330-2019-02-28 + +```rust +#[rustversion::attr(before(1.33), repr(packed))] +#[rustversion::attr(since(1.33), repr(packed(2)))] +struct Six(i16, i32); + +fn main() { + println!("{}", std::mem::align_of::<Six>()); +} +``` + +Augmenting code with `const` as const impls are stabilized in the standard +library. This use of `const` as an attribute is recognized as a special case by +the rustversion::attr macro. + +```rust +use std::time::Duration; + +#[rustversion::attr(since(1.32), const)] +fn duration_as_days(dur: Duration) -> u64 { + dur.as_secs() / 60 / 60 / 24 +} +``` + +<br> + +#### License + +<sup> +Licensed under either of <a href="LICENSE-APACHE">Apache License, Version +2.0</a> or <a href="LICENSE-MIT">MIT license</a> at your option. +</sup> + +<br> + +<sub> +Unless you explicitly state otherwise, any contribution intentionally submitted +for inclusion in this crate by you, as defined in the Apache-2.0 license, shall +be dual licensed as above, without any additional terms or conditions. +</sub> |