Updated to 2.3.0

Author: Oren (electricessence)

DeferredHashSet.cs

@@ -0,0 +1,42 @@
+using System;
+using System.Collections.Generic;
+namespace Open.RandomizationExtensions
+{
+	class DeferredHashSet<T> : HashSet<T>, IDisposable
+	{
+		public DeferredHashSet(IEnumerator<T> source)
+		{
+			Source = source ?? throw new ArgumentNullException(nameof(source));
+		}
+
+		public DeferredHashSet(IEnumerable<T> source)
+			: this((source ?? throw new ArgumentNullException(nameof(source))).GetEnumerator())
+		{
+
+		}
+
+		private readonly IEnumerator<T> Source;
+
+		public new bool Contains(T item)
+		{
+			if (base.Contains(item))
+				return true;
+
+			while(Source.MoveNext())
+			{
+				var i = Source.Current;
+				Add(i);
+				if (item is null ? i is null : item.Equals(i))
+					return true;
+			}
+
+			return false;
+		}
+
+		public void Dispose()
+		{
+			Source.Dispose();
+			this.Clear();
+		}
+	}
+}

Open.RandomizationExtensions.csproj

@@ -14,11 +14,13 @@ Part of the "Open" set of libraries.</Description>
     <RepositoryUrl>https://github.com/electricessence/Open.RandomizationExtensions</RepositoryUrl>
     <RepositoryType>Git</RepositoryType>
     <PackageTags>random select</PackageTags>
-    <Version>2.0.0</Version>
+    <Version>2.3.0</Version>
+		<LangVersion>latest</LangVersion>
+		<Nullable>enable</Nullable>
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Open.MemoryExtensions" Version="2.1.0" />
+    <PackageReference Include="Open.MemoryExtensions" Version="2.3.0" />
   </ItemGroup>
 
 </Project>