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Yes.Infrastructure/ViewEngine/UriTemplateEquivalenceComparer.cs

@@ -0,0 +1,46 @@
+namespace Yes.Infrastructure.ViewEngine
+{
+    public class UriTemplateEquivalenceComparer : IEqualityComparer<UriTemplate>
+    {
+        static UriTemplateEquivalenceComparer _instance;
+        internal static UriTemplateEquivalenceComparer Instance
+        {
+            get
+            {
+                if (_instance == null)
+                {
+                    // lock-free, fine if we allocate more than one
+                    _instance = new UriTemplateEquivalenceComparer();
+                }
+                return _instance;
+            }
+        }
+
+        public bool Equals(UriTemplate x, UriTemplate y)
+        {
+            if (x == null)
+            {
+                return y == null;
+            }
+            return x.IsEquivalentTo(y);
+        }
+        public int GetHashCode(UriTemplate obj)
+        {
+            if (obj == null)
+            {
+                throw new ArgumentNullException(nameof(obj));
+            }
+#pragma warning disable 56506 // obj.xxx is never null
+            // prefer final literal segment (common literal prefixes are common in some scenarios)
+            for (int i = obj.Segments.Count - 1; i >= 0; --i)
+            {
+                if (obj.Segments[i].Nature == UriTemplatePartType.Literal)
+                {
+                    return obj.Segments[i].GetHashCode();
+                }
+            }
+            return obj.Segments.Count + obj.Queries.Count;
+#pragma warning restore 56506
+        }
+    }
+}