diff --git a/lib/netstd/Thrift/Collections/TCollections.cs b/lib/netstd/Thrift/Collections/TCollections.cs
index b386c37..21ee3bb 100644
--- a/lib/netstd/Thrift/Collections/TCollections.cs
+++ b/lib/netstd/Thrift/Collections/TCollections.cs
@@ -99,8 +99,7 @@
 
             foreach (var obj in enumerable)
             {
-                var enum2 = obj as IEnumerable;
-                var objHash = enum2 == null ? obj.GetHashCode() : GetHashCode(enum2);
+                var objHash = (obj is IEnumerable enum2) ? GetHashCode(enum2) : obj.GetHashCode();
 
                 unchecked
                 {
diff --git a/lib/netstd/Thrift/Collections/THashSet.cs b/lib/netstd/Thrift/Collections/THashSet.cs
index 8dfb9e3..25fcf10 100644
--- a/lib/netstd/Thrift/Collections/THashSet.cs
+++ b/lib/netstd/Thrift/Collections/THashSet.cs
@@ -32,8 +32,13 @@
 
         public THashSet(int capacity)
         {
-            // TODO: uncomment capacity when NET Standard also implements it
-            Items = new HashSet<T>(/*capacity*/);
+            #if NET5_0
+            Items = new HashSet<T>(capacity);
+            #elif NETFRAMEWORK || NETSTANDARD
+            Items = new HashSet<T>(/*capacity not supported*/);
+            #else
+            #error Unknown platform
+            #endif
         }
 
         public int Count => Items.Count;