rust/src/test/compile-fail/unboxed-closures-failed-recursive-fn-2.rs
Niko Matsakis 5a39a0d266 To handle more complex cases, modify the deferred call handler to be
specialized to closures, and invoke them as soon as we know the
closure kind. I thought initially we would need a fixed-point
inference algorithm but it appears I was mistaken, so we can do this.
2015-02-01 06:13:06 -05:00

40 lines
1.2 KiB
Rust

// Copyright 2015 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 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
// Various unsuccessful attempts to put the unboxed closure kind
// inference into an awkward position that might require fixed point
// iteration (basically where inferring the kind of a closure `c`
// would require knowing the kind of `c`). I currently believe this is
// impossible.
fn a() {
let mut closure0 = None;
let vec = vec!(1, 2, 3);
loop {
{
let closure1 = || {
match closure0.take() {
Some(c) => {
return c();
//~^ ERROR the type of this value must be known in this context
}
None => { }
}
};
closure1();
}
closure0 = || vec;
}
}
fn main() { }