First commit

src/Discord.Net.Core/Utils/Cache.cs

@@ -0,0 +1,23 @@
+using System;
+using System.Reflection;
+using System.Threading.Tasks;
+using TId = Discord.IEntity<ulong>;
+
+
+namespace Discord
+{
+    public abstract class Cache<T> where T : IEntity<ulong> 
+    {
+        public bool IsCached => Value != null;
+        public TId Id { get; }
+        public T Value { get; }
+
+        protected Cache(TId id)
+        {
+            Id = id;
+        }
+
+        public async Task<T> DownloadAsync() => typeof(T).GetRuntimeMethod("DownloadAsync",{ulong id});
+        public async Task<T> GetOrDownloadAsync() => IsCached ? Value : await DownloadAsync();
+    }
+}