// Copyright 2012-2014 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 or the MIT license // , at your // option. This file may not be copied, modified, or distributed // except according to those terms. // trait to_str { fn to_string_(&self) -> String; } impl to_str for isize { fn to_string_(&self) -> String { self.to_string() } } impl to_str for Vec { fn to_string_(&self) -> String { format!("[{}]", self.iter() .map(|e| e.to_string_()) .collect::>() .join(", ")) } } pub fn main() { assert_eq!(1.to_string_(), "1".to_string()); assert_eq!((vec!(2, 3, 4)).to_string_(), "[2, 3, 4]".to_string()); fn indirect(x: T) -> String { format!("{}!", x.to_string_()) } assert_eq!(indirect(vec!(10, 20)), "[10, 20]!".to_string()); fn indirect2(x: T) -> String { indirect(x) } assert_eq!(indirect2(vec!(1)), "[1]!".to_string()); }