# System.Collections.Immutable

``` diff
 namespace System.Collections.Immutable {
     public static class ImmutableArray {
+        public static ImmutableArray<TSource> ToImmutableArray<TSource>(this ImmutableArray<TSource>.Builder builder);
     }
     public struct ImmutableArray<T> : ICollection, ICollection<T>, IEnumerable, IEnumerable<T>, IEquatable<ImmutableArray<T>>, IImmutableList<T>, IList, IList<T>, IReadOnlyCollection<T>, IReadOnlyList<T>, IStructuralComparable, IStructuralEquatable {
+        public ReadOnlyMemory<T> AsMemory();
+        public ReadOnlySpan<T> AsSpan();
     }
     public static class ImmutableDictionary {
+        public static ImmutableDictionary<TKey, TValue> ToImmutableDictionary<TKey, TValue>(this ImmutableDictionary<TKey, TValue>.Builder builder);
     }
     public static class ImmutableHashSet {
+        public static ImmutableHashSet<TSource> ToImmutableHashSet<TSource>(this ImmutableHashSet<TSource>.Builder builder);
     }
     public static class ImmutableList {
+        public static ImmutableList<TSource> ToImmutableList<TSource>(this ImmutableList<TSource>.Builder builder);
     }
     public static class ImmutableSortedDictionary {
+        public static ImmutableSortedDictionary<TKey, TValue> ToImmutableSortedDictionary<TKey, TValue>(this ImmutableSortedDictionary<TKey, TValue>.Builder builder);
     }
     public static class ImmutableSortedSet {
+        public static ImmutableSortedSet<TSource> ToImmutableSortedSet<TSource>(this ImmutableSortedSet<TSource>.Builder builder);
     }
 }
```