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// MIT License // // Copyright (c) 2018 Guillaume Gomez // // Permission is hereby granted, free of charge, to any person obtaining a copy // of this software and associated documentation files (the "Software"), to deal // in the Software without restriction, including without limitation the rights // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell // copies of the Software, and to permit persons to whom the Software is // furnished to do so, subject to the following conditions: // // The above copyright notice and this permission notice shall be included in all // copies or substantial portions of the Software. // // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE // SOFTWARE. /// You miss C-like ternary conditions? Why not having them in Rust then? /// /// ``` /// # #[macro_use] extern crate macro_utils; /// let y = 4; /// let x = tern_c! { (y & 1 == 0) ? { "even" } : { "odd" } }; /// /// println!("{} is {}", y, x); /// ``` #[macro_export] macro_rules! tern_c { (($cond:expr) ? { $if_expr:expr } : { $else_expr:expr }) => { if $cond { $if_expr } else { $else_expr } }; } #[test] fn tern_c() { let y = 4; let x = tern_c! { (y & 1 == 0) ? { "it's even" } : { "it's odd" } }; assert_eq!(x, "it's even"); }