std/datetime.d

@@ -1075,6 +1075,68 @@ public:
         //assert(ist.opCmp(ist) == 0);
     }
 
+    /**
+     * Returns: A hash of the $(LREF SysTime)
+     */
+    size_t toHash() const @nogc pure nothrow @safe
+    {
+        static if (is(size_t == ulong))
+        {
+            return _stdTime;
+        }
+        else
+        {
+            // MurmurHash2
+            enum ulong m = 0xc6a4a7935bd1e995UL;
+            enum ulong n = m * 16;
+            enum uint r = 47;
+
+            ulong k = _stdTime;
+            k *= m;
+            k ^= k >> r;
+            k *= m;
+
+            ulong h = n;
+            h ^= k;
+            h *= m;
+
+            return cast(size_t) h;
+        }
+    }
+
+    @safe unittest
+    {
+        assert(SysTime(0).toHash == SysTime(0).toHash);
+        assert(SysTime(DateTime(2000, 1, 1)).toHash == SysTime(DateTime(2000, 1, 1)).toHash);
+        assert(SysTime(DateTime(2000, 1, 1)).toHash != SysTime(DateTime(2000, 1, 2)).toHash);
+
+        // test that timezones aren't taken into account
+        assert(SysTime(0, LocalTime()).toHash == SysTime(0, LocalTime()).toHash);
+        assert(SysTime(0, LocalTime()).toHash == SysTime(0, UTC()).toHash);
+        assert(
+            SysTime(
+                DateTime(2000, 1, 1), LocalTime()
+            ).toHash == SysTime(
+                DateTime(2000, 1, 1), LocalTime()
+            ).toHash
+        );
+        immutable zone = new SimpleTimeZone(dur!"minutes"(60));
+        assert(
+            SysTime(
+                DateTime(2000, 1, 1, 1), zone
+            ).toHash == SysTime(
+                DateTime(2000, 1, 1), UTC()
+            ).toHash
+        );
+        assert(
+            SysTime(
+                DateTime(2000, 1, 1), zone
+            ).toHash != SysTime(
+                DateTime(2000, 1, 1), UTC()
+            ).toHash
+        );
+    }
+
     /++
         Year of the Gregorian Calendar. Positive numbers are A.D. Non-positive
         are B.C.