1# cfg-if
2
3[Documentation](https://docs.rs/cfg-if)
4
5A macro to ergonomically define an item depending on a large number of #[cfg]
6parameters. Structured like an if-else chain, the first matching branch is the
7item that gets emitted.
8
9```toml
10[dependencies]
11cfg-if = "0.1"
12```
13
14## Example
15
16```rust
17cfg_if::cfg_if! {
18    if #[cfg(unix)] {
19        fn foo() { /* unix specific functionality */ }
20    } else if #[cfg(target_pointer_width = "32")] {
21        fn foo() { /* non-unix, 32-bit functionality */ }
22    } else {
23        fn foo() { /* fallback implementation */ }
24    }
25}
26
27fn main() {
28    foo();
29}
30```
31
32# License
33
34This project is licensed under either of
35
36 * Apache License, Version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or
37   http://www.apache.org/licenses/LICENSE-2.0)
38 * MIT license ([LICENSE-MIT](LICENSE-MIT) or
39   http://opensource.org/licenses/MIT)
40
41at your option.
42
43### Contribution
44
45Unless you explicitly state otherwise, any contribution intentionally submitted
46for inclusion in `cfg-if` by you, as defined in the Apache-2.0 license, shall be
47dual licensed as above, without any additional terms or conditions.
48