Improve doc wording for retain on some collections

Author: allgoewer

library/alloc/src/collections/binary_heap.rs

@@ -779,7 +779,7 @@ impl<T: Ord> BinaryHeap<T> {
 
     /// Retains only the elements specified by the predicate.
     ///
-    /// In other words, remove all elements `e` such that `f(&e)` returns
+    /// In other words, remove all elements `e` for which `f(&e)` returns
     /// `false`. The elements are visited in unsorted (and unspecified) order.
     ///
     /// # Examples

library/alloc/src/collections/btree/map.rs

@@ -963,7 +963,7 @@ impl<K, V> BTreeMap<K, V> {
 
     /// Retains only the elements specified by the predicate.
     ///
-    /// In other words, remove all pairs `(k, v)` such that `f(&k, &mut v)` returns `false`.
+    /// In other words, remove all pairs `(k, v)` for which `f(&k, &mut v)` returns `false`.
     /// The elements are visited in ascending key order.
     ///
     /// # Examples

library/alloc/src/collections/btree/set.rs

@@ -873,7 +873,7 @@ impl<T> BTreeSet<T> {
 
     /// Retains only the elements specified by the predicate.
     ///
-    /// In other words, remove all elements `e` such that `f(&e)` returns `false`.
+    /// In other words, remove all elements `e` for which `f(&e)` returns `false`.
     /// The elements are visited in ascending order.
     ///
     /// # Examples

library/alloc/src/collections/vec_deque/mod.rs

@@ -2119,7 +2119,7 @@ impl<T, A: Allocator> VecDeque<T, A> {
 
     /// Retains only the elements specified by the predicate.
     ///
-    /// In other words, remove all elements `e` such that `f(&e)` returns false.
+    /// In other words, remove all elements `e` for which `f(&e)` returns false.
     /// This method operates in place, visiting each element exactly once in the
     /// original order, and preserves the order of the retained elements.
     ///
@@ -2158,7 +2158,7 @@ impl<T, A: Allocator> VecDeque<T, A> {
 
     /// Retains only the elements specified by the predicate.
     ///
-    /// In other words, remove all elements `e` such that `f(&e)` returns false.
+    /// In other words, remove all elements `e` for which `f(&e)` returns false.
     /// This method operates in place, visiting each element exactly once in the
     /// original order, and preserves the order of the retained elements.
     ///

library/alloc/src/vec/mod.rs

@@ -1424,7 +1424,7 @@ impl<T, A: Allocator> Vec<T, A> {
 
     /// Retains only the elements specified by the predicate.
     ///
-    /// In other words, remove all elements `e` such that `f(&e)` returns `false`.
+    /// In other words, remove all elements `e` for which `f(&e)` returns `false`.
     /// This method operates in place, visiting each element exactly once in the
     /// original order, and preserves the order of the retained elements.
     ///

library/std/src/collections/hash/map.rs

@@ -621,7 +621,7 @@ impl<K, V, S> HashMap<K, V, S> {
 
     /// Retains only the elements specified by the predicate.
     ///
-    /// In other words, remove all pairs `(k, v)` such that `f(&k, &mut v)` returns `false`.
+    /// In other words, remove all pairs `(k, v)` for which `f(&k, &mut v)` returns `false`.
     /// The elements are visited in unsorted (and unspecified) order.
     ///
     /// # Examples

library/std/src/collections/hash/set.rs

@@ -300,7 +300,7 @@ impl<T, S> HashSet<T, S> {
 
     /// Retains only the elements specified by the predicate.
     ///
-    /// In other words, remove all elements `e` such that `f(&e)` returns `false`.
+    /// In other words, remove all elements `e` for which `f(&e)` returns `false`.
     /// The elements are visited in unsorted (and unspecified) order.
     ///
     /// # Examples