//! [![github]](https://github.com/dtolnay/rustversion) [![crates-io]](https://crates.io/crates/rustversion) [![docs-rs]](https://docs.rs/rustversion)
//!
//! [github]: https://img.shields.io/badge/github-8da0cb?style=for-the-badge&labelColor=555555&logo=github
//! [crates-io]: https://img.shields.io/badge/crates.io-fc8d62?style=for-the-badge&labelColor=555555&logo=rust
//! [docs-rs]: https://img.shields.io/badge/docs.rs-66c2a5?style=for-the-badge&labelColor=555555&logo=docs.rs
//!
//! <br>
//!
//! 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
//!
//! <br>
//!
//! # Selectors
//!
//! - <p style="margin-left:50px;text-indent:-50px">
//! <b><code>#[rustversion::stable]</code></b>
//! —<br>
//! True on any stable compiler.
//! </p>
//!
//! - <p style="margin-left:50px;text-indent:-50px">
//! <b><code>#[rustversion::stable(1.34)]</code></b>
//! —<br>
//! True on exactly the specified stable compiler.
//! </p>
//!
//! - <p style="margin-left:50px;text-indent:-50px">
//! <b><code>#[rustversion::beta]</code></b>
//! —<br>
//! True on any beta compiler.
//! </p>
//!
//! - <p style="margin-left:50px;text-indent:-50px">
//! <b><code>#[rustversion::nightly]</code></b>
//! —<br>
//! True on any nightly compiler or dev build.
//! </p>
//!
//! - <p style="margin-left:50px;text-indent:-50px">
//! <b><code>#[rustversion::nightly(2019-01-01)]</code></b>
//! —<br>
//! True on exactly one nightly.
//! </p>
//!
//! - <p style="margin-left:50px;text-indent:-50px">
//! <b><code>#[rustversion::since(1.34)]</code></b>
//! —<br>
//! True on that stable release and any later compiler, including beta and
//! nightly.
//! </p>
//!
//! - <p style="margin-left:50px;text-indent:-50px">
//! <b><code>#[rustversion::since(2019-01-01)]</code></b>
//! —<br>
//! True on that nightly and all newer ones.
//! </p>
//!
//! - <p style="margin-left:50px;text-indent:-50px">
//! <b><code>#[rustversion::before(</code></b><i>version or date</i><b><code>)]</code></b>
//! —<br>
//! Negative of <i>#[rustversion::since(...)]</i>.
//! </p>
//!
//! - <p style="margin-left:50px;text-indent:-50px">
//! <b><code>#[rustversion::not(</code></b><i>selector</i><b><code>)]</code></b>
//! —<br>
//! Negative of any selector; for example <i>#[rustversion::not(nightly)]</i>.
//! </p>
//!
//! - <p style="margin-left:50px;text-indent:-50px">
//! <b><code>#[rustversion::any(</code></b><i>selectors...</i><b><code>)]</code></b>
//! —<br>
//! True if any of the comma-separated selectors is true; for example
//! <i>#[rustversion::any(stable, beta)]</i>.
//! </p>
//!
//! - <p style="margin-left:50px;text-indent:-50px">
//! <b><code>#[rustversion::all(</code></b><i>selectors...</i><b><code>)]</code></b>
//! —<br>
//! True if all of the comma-separated selectors are true; for example
//! <i>#[rustversion::all(since(1.31), before(1.34))]</i>.
//! </p>
//!
//! - <p style="margin-left:50px;text-indent:-50px">
//! <b><code>#[rustversion::attr(</code></b><i>selector</i><b><code>, </code></b><i>attribute</i><b><code>)]</code></b>
//! —<br>
//! For conditional inclusion of attributes; analogous to
//! <code>cfg_attr</code>.
//! </p>
//!
//! <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
//!
//! ```
//! # trait MyTrait {}
//! #
//! #[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
//!
//! ```
//! #[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.
//!
//! ```
//! use std::time::Duration;
//!
//! #[rustversion::attr(since(1.32), const)]
//! fn duration_as_days(dur: Duration) -> u64 {
//! dur.as_secs() / 60 / 60 / 24
//! }
//! ```
//!
//! <br>
extern crate proc_macro;
use crate Error;
use crate Version;
use TokenStream;
const RUSTVERSION: Version = include!;