rust/src/test/ui/unboxed-closures/unboxed-closures-mutated-upvar-from-fn-closure.rs
2019-04-22 08:40:08 +01:00

15 lines
264 B
Rust

// Test that a by-ref `FnMut` closure gets an error when it tries to
// mutate a value.
fn call<F>(f: F) where F : Fn() {
f();
}
fn main() {
let mut counter = 0;
call(|| {
counter += 1;
//~^ ERROR cannot assign to `counter`
});
}