rust/src/test/run-pass/const-fn.rs
2016-03-10 12:50:12 +01:00

50 lines
1.2 KiB
Rust

// 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_indexing)]
const fn add(x: u32, y: u32) -> u32 {
x + y
}
const fn sub(x: u32, y: u32) -> u32 {
x - y
}
const unsafe fn div(x: u32, y: u32) -> u32 {
x / y
}
const fn generic<T>(t: T) -> T {
t
}
const fn generic_arr<T: Copy>(t: [T; 1]) -> T {
t[0]
}
const SUM: u32 = add(44, 22);
const DIFF: u32 = sub(44, 22);
const DIV: u32 = unsafe{div(44, 22)};
fn main() {
assert_eq!(SUM, 66);
assert!(SUM != 88);
assert_eq!(DIFF, 22);
assert_eq!(DIV, 2);
let _: [&'static str; sub(100, 99) as usize] = ["hi"];
let _: [&'static str; generic(1)] = ["hi"];
let _: [&'static str; generic_arr([1])] = ["hi"];
}