}
}
+// Specializable trait for implementing ToOwned::clone_into. This is
+// public in the crate and has the Allocator parameter so that
+// vec::clone_from use it too.
+#[cfg(not(no_global_oom_handling))]
+pub(crate) trait SpecCloneIntoVec<T, A: Allocator> {
+ fn clone_into(&self, target: &mut Vec<T, A>);
+}
+
+#[cfg(not(no_global_oom_handling))]
+impl<T: Clone, A: Allocator> SpecCloneIntoVec<T, A> for [T] {
+ default fn clone_into(&self, target: &mut Vec<T, A>) {
+ // drop anything in target that will not be overwritten
+ target.truncate(self.len());
+
+ // target.len <= self.len due to the truncate above, so the
+ // slices here are always in-bounds.
+ let (init, tail) = self.split_at(target.len());
+
+ // reuse the contained values' allocations/resources.
+ target.clone_from_slice(init);
+ target.extend_from_slice(tail);
+ }
+}
+
+#[cfg(not(no_global_oom_handling))]
+impl<T: Copy, A: Allocator> SpecCloneIntoVec<T, A> for [T] {
+ fn clone_into(&self, target: &mut Vec<T, A>) {
+ target.clear();
+ target.extend_from_slice(self);
+ }
+}
+
#[cfg(not(no_global_oom_handling))]
#[stable(feature = "rust1", since = "1.0.0")]
impl<T: Clone> ToOwned for [T] {
}
fn clone_into(&self, target: &mut Vec<T>) {
- // drop anything in target that will not be overwritten
- target.truncate(self.len());
-
- // target.len <= self.len due to the truncate above, so the
- // slices here are always in-bounds.
- let (init, tail) = self.split_at(target.len());
-
- // reuse the contained values' allocations/resources.
- target.clone_from_slice(init);
- target.extend_from_slice(tail);
+ SpecCloneIntoVec::clone_into(self, target);
}
}