// Copyright 2018 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. // Issue 27282: Example 1: This sidesteps the AST checks disallowing // mutable borrows in match guards by hiding the mutable borrow in a // guard behind a move (of the ref mut pattern id) within a closure. // // This example is not rejected by AST borrowck (and then reliably // segfaults when executed). #![feature(nll)] fn main() { match Some(&4) { None => {}, ref mut foo if { (|| { let bar = foo; bar.take() })(); false } => {}, //~^ ERROR cannot move out of borrowed content [E0507] Some(s) => std::process::exit(*s), } }