# cfg-if
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[Documentation](http://alexcrichton.com/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
#[macro_use]
extern crate 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
`cfg-if` is primarily distributed under the terms of both the MIT license and
the Apache License (Version 2.0), with portions covered by various BSD-like
licenses.
See LICENSE-APACHE, and LICENSE-MIT for details.