Improve performance of partition

std/algorithm/sorting.d

@@ -362,6 +362,33 @@ Range partition(alias predicate,
     {
         // Inspired from www.stepanovpapers.com/PAM3-partition_notes.pdf,
         // section "Bidirectional Partition Algorithm (Hoare)"
+        static if (isDynamicArray!Range)
+        {
+            // For dynamic arrays prefer index-based manipulation
+            if (!r.length) return r;
+            size_t lo = 0, hi = r.length - 1;
+            for (;;)
+            {
+                for (;;)
+                {
+                    if (lo > hi) return r[lo .. $];
+                    if (!pred(r[lo])) break;
+                    ++lo;
+                }
+                // found the left bound
+                assert(lo <= hi);
+                for (;;)
+                {
+                    if (lo == hi) return r[lo .. $];
+                    if (pred(r[hi])) break;
+                    --hi;
+                }
+                // found the right bound, swap & make progress
+                swap(r[lo++], r[hi--]);
+            }
+        }
+        else
+        {
             auto result = r;
             for (;;)
             {
@@ -396,6 +423,7 @@ Range partition(alias predicate,
                 r.popBack();
             }
         }
+    }
 }
 
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