rust/tests/ui/unboxed-closures/unboxed-closures-static-call-wrong-trait.rs

#![feature(unboxed_closures, tuple_trait)]

fn to_fn_mut<A:std::marker::Tuple,F:FnMut<A>>(f: F) -> F { f }

fn main() {
    let mut_ = to_fn_mut(|x| x);
    mut_.call((0, )); //~ ERROR no method named `call` found
}