// Copyright 2012 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. fn reproduce(t: T) -> @fn() -> T { let result: @fn() -> T = || t; result } fn main() { // type of x is the variable X, // with the lower bound @mut int let x = @mut 3; // type of r is @fn() -> X let r = reproduce(x); // Requires that X be a subtype of // @mut int. let f: @mut int = r(); // Bad. let h: @int = r(); //~ ERROR (values differ in mutability) }