1 files changed, 20 insertions, 1 deletions
diff --git a/library/core/src/iter/adapters/take.rs b/library/core/src/iter/adapters/take.rs
index 58a0b9d7b..d947c7b0e 100644
--- a/library/core/src/iter/adapters/take.rs
+++ b/library/core/src/iter/adapters/take.rs
@@ -75,7 +75,6 @@ where
     #[inline]
     fn try_fold<Acc, Fold, R>(&mut self, init: Acc, fold: Fold) -> R
     where
-        Self: Sized,
         Fold: FnMut(Acc, Self::Item) -> R,
         R: Try<Output = Acc>,
     {
@@ -101,6 +100,26 @@ where
     impl_fold_via_try_fold! { fold -> try_fold }
 
     #[inline]
+    fn for_each<F: FnMut(Self::Item)>(mut self, f: F) {
+        // The default implementation would use a unit accumulator, so we can
+        // avoid a stateful closure by folding over the remaining number
+        // of items we wish to return instead.
+        fn check<'a, Item>(
+            mut action: impl FnMut(Item) + 'a,
+        ) -> impl FnMut(usize, Item) -> Option<usize> + 'a {
+            move |more, x| {
+                action(x);
+                more.checked_sub(1)
+            }
+        }
+
+        let remaining = self.n;
+        if remaining > 0 {
+            self.iter.try_fold(remaining - 1, check(f));
+        }
+    }
+
+    #[inline]
     #[rustc_inherit_overflow_checks]
     fn advance_by(&mut self, n: usize) -> Result<(), usize> {
         let min = self.n.min(n);