// run-pass // Test that we are able to infer a suitable kind for this closure // that is just called (`FnMut`). fn main() { let mut counter = 0; { // Here this must be inferred to FnMut so that it can mutate counter: let mut tick1 = || counter += 1; // In turn, tick2 must be inferred to FnMut so that it can call tick1: let mut tick2 = || { tick1(); tick1(); }; tick2(); } assert_eq!(counter, 2); }