| // 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. |
| |
| use std::ops::Index; |
| |
| pub trait Array2D: Index<usize> { |
| fn rows(&self) -> usize; |
| fn columns(&self) -> usize; |
| fn get<'a>(&'a self, y: usize, x: usize) -> Option<&'a <Self as Index<usize>>::Output> { |
| if y >= self.rows() || x >= self.columns() { |
| return None; |
| } |
| let i = y * self.columns() + x; |
| let indexer = &(*self as &Index<usize, Output = <Self as Index<usize>>::Output>); |
| //~^ERROR non-primitive cast |
| Some(indexer.index(i)) |
| } |
| } |
| |
| fn main() {} |