Method swap_getitem

crates/vm/src/builtins/type.rs:318–327

(&self, new_getitem: Option<PyRef<PyFunction>>, vm: Option<&VirtualMachine>)

    #[inline]
    fn swap_getitem(&self, new_getitem: Option<PyRef<PyFunction>>, vm: Option<&VirtualMachine>) {
        if let Some(vm) = vm {
            self.getitem.swap_to_temporary_refs(new_getitem, vm);
            return;
        }
        // SAFETY: old value is moved to `retired`, so it stays alive while
        // concurrent readers may still hold borrowed references.
        let old = unsafe { self.getitem.swap(new_getitem) };
        self.retire_old_function(old);
    }

    #[inline]
    fn invalidate_for_type_modified(&self) {