1 #![feature(unboxed_closures, tuple_trait)]
5 fn to_fn_once
<A
:std
::marker
::Tuple
,F
:FnOnce
<A
>>(f
: F
) -> F { f }
9 to_fn_once(move|| { x = 2; }
);
10 //~^ ERROR: cannot assign to `x`, as it is not declared as mutable
12 let s
= std
::io
::stdin();
13 to_fn_once(move|| { s.read_to_end(&mut Vec::new()); }
);
14 //~^ ERROR: cannot borrow `s` as mutable, as it is not declared as mutable