Skip to content
A if/elif-like macro for Rust #[cfg] statements
Branch: master
Clone or download
Type Name Latest commit message Commit time
Failed to load latest commit information.
.github/workflows Another attempt at gh-pages Sep 26, 2019
src Add a test for the body of an `impl` Sep 24, 2019
tests Update xcrate test to 2018 Jun 21, 2019
.gitignore Initial commit Jul 8, 2015
Cargo.toml Bump to 0.1.10 Sep 24, 2019
LICENSE-APACHE Add missing license files Feb 21, 2017
LICENSE-MIT Add missing license files Feb 21, 2017 Ok no badge for now Sep 6, 2019



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.

cfg-if = "0.1"


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() {


This project is licensed under either of

at your option.


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.

You can’t perform that action at this time.