rust/src/test/run-pass/trait-inheritance-num5.rs
Niko Matsakis dbf994bbaf Make RFC 1214 warnings into errors, and rip out the "warn or err"
associated machinery. Future such attempts should go through lints
anyhow.

There is a fair amount of fallout in the compile-fail tests, as WF
checking now occurs earlier in the process.
2015-12-18 12:41:02 -05:00

36 lines
994 B
Rust

// Copyright 2012 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.
// pretty-expanded FIXME #23616
pub trait NumCast: Sized {
fn from(i: i32) -> Option<Self>;
}
pub trait NumExt: PartialEq + NumCast {}
impl NumExt for f32 {}
impl NumExt for isize {}
impl NumCast for f32 {
fn from(i: i32) -> Option<f32> { Some(i as f32) }
}
impl NumCast for isize {
fn from(i: i32) -> Option<isize> { Some(i as isize) }
}
fn num_eq_one<T:NumExt>() -> T {
NumCast::from(1).unwrap()
}
pub fn main() {
num_eq_one::<isize>(); // you need to actually use the function to trigger the ICE
}