src/test/ui/issues/issue-21600.stderr

   1 error[E0596]: cannot borrow `x` as mutable, as it is a captured variable in a `Fn` closure
   2   --> $DIR/issue-21600.rs:14:20
   3    |
   4 LL | fn call_it<F>(f: F) where F: Fn() { f(); }
   5    |                  - change this to accept `FnMut` instead of `Fn`
   6 ...
   7 LL |         call_it(|| x.gen_mut());
   8    |         ------- -- ^^^^^^^^^^^ cannot borrow as mutable
   9    |         |       |
  10    |         |       in this closure
  11    |         expects `Fn` instead of `FnMut`
  12
  13 error[E0596]: cannot borrow `x` as mutable, as it is a captured variable in a `Fn` closure
  14   --> $DIR/issue-21600.rs:14:17
  15    |
  16 LL | fn call_it<F>(f: F) where F: Fn() { f(); }
  17    |                  - change this to accept `FnMut` instead of `Fn`
  18 ...
  19 LL |     call_it(|| {
  20    |     ------- -- in this closure
  21    |     |
  22    |     expects `Fn` instead of `FnMut`
  23 LL |         call_it(|| x.gen());
  24 LL |         call_it(|| x.gen_mut());
  25    |                 ^^ - mutable borrow occurs due to use of `x` in closure
  26    |                 |
  27    |                 cannot borrow as mutable
  28
  29 error: aborting due to 2 previous errors
  30
  31 For more information about this error, try `rustc --explain E0596`.