1error[E0596]: cannot borrow `tick1` as mutable, as it is not declared as mutable 2 --> $DIR/unboxed-closures-infer-fnmut-calling-fnmut-no-mut.rs:16:9 3 | 4LL | let tick1 = || { 5 | ----- help: consider changing this to be mutable: `mut tick1` 6LL | counter += 1; 7 | ------- calling `tick1` requires mutable binding due to mutable borrow of `counter` 8... 9LL | tick1(); 10 | ^^^^^ cannot borrow as mutable 11 12error[E0596]: cannot borrow `tick2` as mutable, as it is not declared as mutable 13 --> $DIR/unboxed-closures-infer-fnmut-calling-fnmut-no-mut.rs:19:5 14 | 15LL | let tick2 = || { 16 | ----- help: consider changing this to be mutable: `mut tick2` 17LL | tick1(); 18 | ----- calling `tick2` requires mutable binding due to mutable borrow of `tick1` 19... 20LL | tick2(); 21 | ^^^^^ cannot borrow as mutable 22 23error: aborting due to 2 previous errors 24 25For more information about this error, try `rustc --explain E0596`. 26