Declare Fill for IList<T> not T[]

X10D/src/Collections/ArrayExtensions.cs

@@ -87,28 +87,6 @@ public static class ArrayExtensions
         Array.Clear(array, index, length);
     }
 
-    /// <summary>
-    ///     Assigns the given value to each element of the array.
-    /// </summary>
-    /// <param name="array">The array to be filled.</param>
-    /// <param name="value">The value to assign to each array element.</param>
-    /// <typeparam name="T">The type of the elements in the array.</typeparam>
-    /// <exception cref="ArgumentNullException"><paramref name="array" /> is <see langword="null" />.</exception>
-    public static void Fill<T>(this T?[] array, T value)
-    {
-        if (array is null)
-        {
-            throw new ArgumentNullException(nameof(array));
-        }
-
-        if (array.Length == 0)
-        {
-            return;
-        }
-
-        Array.Fill(array, value);
-    }
-
     /// <summary>
     ///     Assigns the given value to the elements of the array which are within the range of <paramref name="startIndex" />
     ///     (inclusive) and the next <paramref name="count" /> number of indices.

X10D/src/Collections/ListExtensions.cs

@@ -5,6 +5,26 @@
 /// </summary>
 public static class ListExtensions
 {
+    /// <summary>
+    ///     Assigns the given value to each element of the list.
+    /// </summary>
+    /// <param name="source">The list to be filled.</param>
+    /// <param name="value">The value to assign to each list element.</param>
+    /// <typeparam name="T">The type of the elements in the list.</typeparam>
+    /// <exception cref="ArgumentNullException"><paramref name="source" /> is <see langword="null" />.</exception>
+    public static void Fill<T>(this IList<T> source, T value)
+    {
+        if (source is null)
+        {
+            throw new ArgumentNullException(nameof(source));
+        }
+
+        for (var i = 0; i < source.Count; i++)
+        {
+            source[i] = value;
+        }
+    }
+
     /// <summary>
     ///     Returns a random element from the current list using a specified <see cref="System.Random" /> instance.
     /// </summary>