// Copyright 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. struct StringBuffer { s: ~str } impl StringBuffer { pub fn append(&mut self, v: &str) { self.s.push_str(v); } } fn to_str(sb: StringBuffer) -> ~str { sb.s } pub fn main() { let mut sb = StringBuffer {s: ~""}; sb.append("Hello, "); sb.append("World!"); let str = to_str(sb); assert_eq!(str, ~"Hello, World!"); }