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# cfg-if
A macro to ergonomically define an item depending on a large number of #[cfg]
parameters. Structured like an if-else chain, the first matching branch is the
item that gets emitted.
```toml
[dependencies]
cfg-if = "0.1"
```
## Example
```rust
cfg_if::cfg_if! {
if #[cfg(unix)] {
fn foo() { /* unix specific functionality */ }
} else if #[cfg(target_pointer_width = "32")] {
fn foo() { /* non-unix, 32-bit functionality */ }
} else {
fn foo() { /* fallback implementation */ }
}
}
fn main() {
foo();
}
```
# License
This project is licensed under either of
* Apache License, Version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or
* MIT license ([LICENSE-MIT](LICENSE-MIT) or
at your option.
### Contribution
Unless you explicitly state otherwise, any contribution intentionally submitted
for inclusion in `cfg-if` by you, as defined in the Apache-2.0 license, shall be
dual licensed as above, without any additional terms or conditions.