Rollup merge of #41249 - GuillaumeGomez:rustdoc-render, r=steveklabnik,frewsxcv

[rust.git] / src / libcollections / vec.rs

diff --git a/src/libcollections/vec.rs b/src/libcollections/vec.rs
index be613e06b02e87e5c845660aaff657f55496896c..8824185d2809b1c5659fc2c7e98ebdcc898b6628 100644 (file)
--- a/src/libcollections/vec.rs
+++ b/src/libcollections/vec.rs
@@ -973,6 +973,29 @@ pub fn push(&mut self, value: T) {
         }
     }
 
+    /// Returns a place for insertion at the back of the `Vec`.
+    ///
+    /// Using this method with placement syntax is equivalent to [`push`](#method.push),
+    /// but may be more efficient.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// #![feature(collection_placement)]
+    /// #![feature(placement_in_syntax)]
+    ///
+    /// let mut vec = vec![1, 2];
+    /// vec.place_back() <- 3;
+    /// vec.place_back() <- 4;
+    /// assert_eq!(&vec, &[1, 2, 3, 4]);
+    /// ```
+    #[unstable(feature = "collection_placement",
+               reason = "placement protocol is subject to change",
+               issue = "30172")]
+    pub fn place_back(&mut self) -> PlaceBack<T> {
+        PlaceBack { vec: self }
+    }
+
     /// Removes the last element from a vector and returns it, or [`None`] if it
     /// is empty.
     ///
@@ -1267,29 +1290,6 @@ fn extend_with_element(&mut self, n: usize, value: T) {
     pub fn extend_from_slice(&mut self, other: &[T]) {
         self.spec_extend(other.iter())
     }
-
-    /// Returns a place for insertion at the back of the `Vec`.
-    ///
-    /// Using this method with placement syntax is equivalent to [`push`](#method.push),
-    /// but may be more efficient.
-    ///
-    /// # Examples
-    ///
-    /// ```
-    /// #![feature(collection_placement)]
-    /// #![feature(placement_in_syntax)]
-    ///
-    /// let mut vec = vec![1, 2];
-    /// vec.place_back() <- 3;
-    /// vec.place_back() <- 4;
-    /// assert_eq!(&vec, &[1, 2, 3, 4]);
-    /// ```
-    #[unstable(feature = "collection_placement",
-               reason = "placement protocol is subject to change",
-               issue = "30172")]
-    pub fn place_back(&mut self) -> PlaceBack<T> {
-        PlaceBack { vec: self }
-    }
 }
 
 // Set the length of the vec when the `SetLenOnDrop` value goes out of scope.
@@ -1346,7 +1346,7 @@ pub fn dedup(&mut self) {
     /// # Examples
     ///
     /// ```
-    ///# #![feature(vec_remove_item)]
+    /// # #![feature(vec_remove_item)]
     /// let mut vec = vec![1, 2, 3, 1];
     ///
     /// vec.remove_item(&1);
@@ -1396,16 +1396,7 @@ fn clone(&self) -> Vec<T> {
     }
 
     fn clone_from(&mut self, other: &Vec<T>) {
-        // drop anything in self that will not be overwritten
-        self.truncate(other.len());
-        let len = self.len();
-
-        // reuse the contained values' allocations/resources.
-        self.clone_from_slice(&other[..len]);
-
-        // self.len <= other.len due to the truncate above, so the
-        // slice here is always in-bounds.
-        self.extend_from_slice(&other[len..]);
+        other.as_slice().clone_into(self);
     }
 }
 
@@ -2074,14 +2065,10 @@ fn next(&mut self) -> Option<T> {
 
     #[inline]
     fn size_hint(&self) -> (usize, Option<usize>) {
-        let diff = (self.end as usize) - (self.ptr as usize);
-        let size = mem::size_of::<T>();
-        let exact = diff /
-                    (if size == 0 {
-                         1
-                     } else {
-                         size
-                     });
+        let exact = match self.ptr.offset_to(self.end) {
+            Some(x) => x as usize,
+            None => (self.end as usize).wrapping_sub(self.ptr as usize),
+        };
         (exact, Some(exact))
     }