// run-pass // Test when destructors run in a for loop. The intention is // that the value for each iteration is dropped *after* the loop // body has executed. This is true even when the value is assigned // to a `_` pattern (and hence ignored). use std::cell::Cell; struct Flag<'a>(&'a Cell); impl<'a> Drop for Flag<'a> { fn drop(&mut self) { self.0.set(false) } } fn main() { let alive2 = Cell::new(true); for _i in std::iter::once(Flag(&alive2)) { // The Flag value should be alive in the for loop body assert_eq!(alive2.get(), true); } // The Flag value should be dead outside of the loop assert_eq!(alive2.get(), false); let alive = Cell::new(true); for _ in std::iter::once(Flag(&alive)) { // The Flag value should be alive in the for loop body even if it wasn't // bound by the for loop assert_eq!(alive.get(), true); } // The Flag value should be dead outside of the loop assert_eq!(alive.get(), false); }