default fn spec_extend(&mut self, iterator: I) {
// This is the case for a TrustedLen iterator.
let (low, high) = iterator.size_hint();
- if let Some(high_value) = high {
+ if let Some(additional) = high {
debug_assert_eq!(
low,
- high_value,
+ additional,
"TrustedLen iterator's size hint is not exact: {:?}",
(low, high)
);
- }
- if let Some(additional) = high {
self.reserve(additional);
unsafe {
let mut ptr = self.as_mut_ptr().add(self.len());