| // Copyright 2015 The Rust Project Developers. See the COPYRIGHT |
| // file at the top-level directory of this distribution and at |
| // http://rust-lang.org/COPYRIGHT. |
| // |
| // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or |
| // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license |
| // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your |
| // option. This file may not be copied, modified, or distributed |
| // except according to those terms. |
| |
| // A very basic test of const fn functionality. |
| |
| #![feature(const_fn)] |
| |
| const fn add(x: u32, y: u32) -> u32 { |
| x + y |
| } |
| |
| const fn sub(x: u32, y: u32) -> u32 { |
| x - y |
| } |
| |
| const SUM: u32 = add(44, 22); |
| const DIFF: u32 = sub(44, 22); |
| |
| fn main() { |
| assert_eq!(SUM, 66); |
| assert!(SUM != 88); |
| |
| assert_eq!(DIFF, 22); |
| |
| let _: [&'static str; sub(100, 99) as usize] = ["hi"]; |
| } |