src/vendor/rustc_version/README.md

   1 rustc-version-rs
   2 ==============
   3
   4 A library for querying the version of a `rustc` compiler.
   5
   6 This can be used by build scripts or other tools dealing with Rust sources
   7 to make decisions based on the version of the compiler.
   8
   9 [![Travis-CI Status](https://travis-ci.org/Kimundi/rustc-version-rs.png?branch=master)](https://travis-ci.org/Kimundi/rustc-version-rs)
  10
  11 # Getting Started
  12
  13 [rustc-version-rs is available on crates.io](https://crates.io/crates/rustc_version).
  14 It is recommended to look there for the newest released version, as well as links to the newest builds of the docs.
  15
  16 At the point of the last update of this README, the latest published version could be used like this:
  17
  18 Add the following dependency to your Cargo manifest...
  19
  20 ```toml
  21 [build-dependencies]
  22 rustc_version = "0.2"
  23 ```
  24
  25 ...and see the [docs](http://kimundi.github.io/rustc-version-rs/rustc_version/index.html) for how to use it.
  26
  27 # Example
  28
  29 ```rust
  30 // This could be a cargo build script
  31
  32 extern crate rustc_version;
  33 use rustc_version::{version, version_meta, Channel, Version};
  34
  35 fn main() {
  36     // Assert we haven't travelled back in time
  37     assert!(version().unwrap().major >= 1);
  38
  39     // Set cfg flags depending on release channel
  40     match version_meta().unwrap().channel {
  41         Channel::Stable => {
  42             println!("cargo:rustc-cfg=RUSTC_IS_STABLE");
  43         }
  44         Channel::Beta => {
  45             println!("cargo:rustc-cfg=RUSTC_IS_BETA");
  46         }
  47         Channel::Nightly => {
  48             println!("cargo:rustc-cfg=RUSTC_IS_NIGHTLY");
  49         }
  50         Channel::Dev => {
  51             println!("cargo:rustc-cfg=RUSTC_IS_DEV");
  52         }
  53     }
  54
  55     // Check for a minimum version
  56     if version().unwrap() >= Version::parse("1.4.0").unwrap() {
  57         println!("cargo:rustc-cfg=compiler_has_important_bugfix");
  58     }
  59 }
  60 ```
  61
  62 ## License
  63
  64 Licensed under either of
  65
  66  * Apache License, Version 2.0 ([LICENSE-APACHE](LICENSE-APACHE) or http://www.apache.org/licenses/LICENSE-2.0)
  67  * MIT license ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT)
  68
  69 at your option.
  70
  71 ### Contribution
  72
  73 Unless you explicitly state otherwise, any contribution intentionally submitted
  74 for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any
  75 additional terms or conditions.