src/test/ui/closures/2229_closure_analysis/run_pass/capture-disjoint-field-tuple.rs

   1 // run-pass
   2
   3 // Test that we can immutably borrow an element of a tuple from within a closure,
   4 // while having a mutable borrow to another element of the same tuple outside the closure.
   5
   6 #![feature(capture_disjoint_fields)]
   7 //~^ WARNING: the feature `capture_disjoint_fields` is incomplete
   8 //~| NOTE: `#[warn(incomplete_features)]` on by default
   9 //~| NOTE: see issue #53488 <https://github.com/rust-lang/rust/issues/53488>
  10 #![feature(rustc_attrs)]
  11
  12 fn main() {
  13     let mut t = (10, 10);
  14
  15     let c = || {
  16         println!("{}", t.0);
  17     };
  18
  19     // `c` only captures t.0, therefore mutating t.1 is allowed.
  20     let t1 = &mut t.1;
  21
  22     c();
  23     *t1 = 20;
  24 }