// run-pass // Tests "capabilities" granted by traits that inherit from super- // builtin-kinds, e.g., if a trait requires Send to implement, then // at usage site of that trait, we know we have the Send capability. use std::sync::mpsc::{channel, Sender, Receiver}; trait Foo : Send { } impl Foo for T { } fn foo(val: T, chan: Sender) { chan.send(val).unwrap(); } pub fn main() { let (tx, rx): (Sender, Receiver) = channel(); foo(31337, tx); assert_eq!(rx.recv().unwrap(), 31337); }