src/test/run-pass/bare-fn-implements-fn-mut.rs

   1 // Copyright 2014 The Rust Project Developers. See the COPYRIGHT
   2 // file at the top-level directory of this distribution and at
   3 // http://rust-lang.org/COPYRIGHT.
   4 //
   5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
   6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
   8 // option. This file may not be copied, modified, or distributed
   9 // except according to those terms.
  10
  11 use std::ops::FnMut;
  12
  13 fn call_f<F:FnMut()>(mut f: F) {
  14     f();
  15 }
  16
  17 fn f() {
  18     println!("hello");
  19 }
  20
  21 fn call_g<G:FnMut(String,String) -> String>(mut g: G, x: String, y: String)
  22           -> String {
  23     g(x, y)
  24 }
  25
  26 fn g(mut x: String, y: String) -> String {
  27     x.push_str(&y);
  28     x
  29 }
  30
  31 fn main() {
  32     call_f(f);
  33     assert_eq!(call_g(g, "foo".to_string(), "bar".to_string()),
  34                "foobar");
  35 }