src/test/run-pass/trait-bounds-in-arc.rs

   1 // Copyright 2013-2014 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 // Tests that a heterogeneous list of existential types can be put inside an Arc
  12 // and shared between threads as long as all types fulfill Send.
  13
  14 // ignore-pretty
  15
  16 #![allow(unknown_features)]
  17 #![feature(box_syntax, std_misc)]
  18 #![feature(unboxed_closures)]
  19
  20 use std::sync::Arc;
  21 use std::sync::mpsc::channel;
  22 use std::thread;
  23
  24 trait Pet {
  25     fn name(&self, blk: Box<FnMut(&str)>);
  26     fn num_legs(&self) -> usize;
  27     fn of_good_pedigree(&self) -> bool;
  28 }
  29
  30 struct Catte {
  31     num_whiskers: usize,
  32     name: String,
  33 }
  34
  35 struct Dogge {
  36     bark_decibels: usize,
  37     tricks_known: usize,
  38     name: String,
  39 }
  40
  41 struct Goldfyshe {
  42     swim_speed: usize,
  43     name: String,
  44 }
  45
  46 impl Pet for Catte {
  47     fn name(&self, mut blk: Box<FnMut(&str)>) { blk(&self.name) }
  48     fn num_legs(&self) -> usize { 4 }
  49     fn of_good_pedigree(&self) -> bool { self.num_whiskers >= 4 }
  50 }
  51 impl Pet for Dogge {
  52     fn name(&self, mut blk: Box<FnMut(&str)>) { blk(&self.name) }
  53     fn num_legs(&self) -> usize { 4 }
  54     fn of_good_pedigree(&self) -> bool {
  55         self.bark_decibels < 70 || self.tricks_known > 20
  56     }
  57 }
  58 impl Pet for Goldfyshe {
  59     fn name(&self, mut blk: Box<FnMut(&str)>) { blk(&self.name) }
  60     fn num_legs(&self) -> usize { 0 }
  61     fn of_good_pedigree(&self) -> bool { self.swim_speed >= 500 }
  62 }
  63
  64 pub fn main() {
  65     let catte = Catte { num_whiskers: 7, name: "alonzo_church".to_string() };
  66     let dogge1 = Dogge {
  67         bark_decibels: 100,
  68         tricks_known: 42,
  69         name: "alan_turing".to_string(),
  70     };
  71     let dogge2 = Dogge {
  72         bark_decibels: 55,
  73         tricks_known: 11,
  74         name: "albert_einstein".to_string(),
  75     };
  76     let fishe = Goldfyshe {
  77         swim_speed: 998,
  78         name: "alec_guinness".to_string(),
  79     };
  80     let arc = Arc::new(vec!(box catte  as Box<Pet+Sync+Send>,
  81                             box dogge1 as Box<Pet+Sync+Send>,
  82                             box fishe  as Box<Pet+Sync+Send>,
  83                             box dogge2 as Box<Pet+Sync+Send>));
  84     let (tx1, rx1) = channel();
  85     let arc1 = arc.clone();
  86     let t1 = thread::spawn(move|| { check_legs(arc1); tx1.send(()); });
  87     let (tx2, rx2) = channel();
  88     let arc2 = arc.clone();
  89     let t2 = thread::spawn(move|| { check_names(arc2); tx2.send(()); });
  90     let (tx3, rx3) = channel();
  91     let arc3 = arc.clone();
  92     let t3 = thread::spawn(move|| { check_pedigree(arc3); tx3.send(()); });
  93     rx1.recv();
  94     rx2.recv();
  95     rx3.recv();
  96     t1.join();
  97     t2.join();
  98     t3.join();
  99 }
 100
 101 fn check_legs(arc: Arc<Vec<Box<Pet+Sync+Send>>>) {
 102     let mut legs = 0;
 103     for pet in &*arc {
 104         legs += pet.num_legs();
 105     }
 106     assert!(legs == 12);
 107 }
 108 fn check_names(arc: Arc<Vec<Box<Pet+Sync+Send>>>) {
 109     for pet in &*arc {
 110         // FIXME (#22405): Replace `Box::new` with `box` here when/if possible.
 111         pet.name(Box::new(|name| {
 112             assert!(name.as_bytes()[0] == 'a' as u8 && name.as_bytes()[1] == 'l' as u8);
 113         }))
 114     }
 115 }
 116 fn check_pedigree(arc: Arc<Vec<Box<Pet+Sync+Send>>>) {
 117     for pet in &*arc {
 118         assert!(pet.of_good_pedigree());
 119     }
 120 }