diff --git a/monster/util/flags.d b/monster/util/flags.d
new file mode 100644
index 000000000..997a7122b
--- /dev/null
+++ b/monster/util/flags.d
@@ -0,0 +1,143 @@
+/*
+  Monster - an advanced game scripting language
+  Copyright (C) 2007, 2008  Nicolay Korslund
+  Email: <korslund@gmail.com>
+  WWW: http://monster.snaptoad.com/
+
+  This file (flags.d) is part of the Monster script language package.
+
+  Monster is distributed as free software: you can redistribute it
+  and/or modify it under the terms of the GNU General Public License
+  version 3, as published by the Free Software Foundation.
+
+  This program is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+  General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  version 3 along with this program. If not, see
+  http://www.gnu.org/licenses/ .
+
+ */
+
+module monster.util.flags;
+
+// A generic bitwise flag manager.
+struct Flags(T)
+{
+  T flags;
+
+  void set(T t)
+    { flags |= t; }
+
+  void unset(T t)
+    { flags ^= flags & t; }
+
+  bool has(T t)
+    { return (flags & t) != t; }
+
+  bool hasAny(T t)
+    { return (flags & t) != 0; }
+
+  void set(T t, bool value)
+    {
+      if(value) set(t);
+      else unset(t);
+      assert(has(t) == value);
+    }
+}
+
+unittest
+{
+  Flags!(int) fl;
+
+  assert(fl.flags == 0);
+
+  // Try setting some flags
+  assert(!fl.has(2));
+  fl.set(2);
+  assert(fl.has(2));
+
+  assert(!fl.has(4));
+  fl.set(4, true);
+  assert(fl.has(4));
+
+  assert(fl.flags == 6);
+
+  // Make sure setting them again won't change anything
+  fl.set(2);
+  assert(fl.flags == 6);
+
+  fl.set(4);
+  assert(fl.flags == 6);
+
+  fl.set(2, true);
+  assert(fl.flags == 6);
+
+  fl.set(4, true);
+  assert(fl.flags == 6);
+
+  // Test the has() and hasAny() functions
+  with(fl)
+    {
+      assert( !has(1) ); // 1 is not set
+      assert( has(2) );  // 2 is set
+      assert( !has(3) ); // 2+1 is NOT set, because 1 is missing
+      assert( has(4) );  // 4 is set
+      assert( !has(5) ); // 4+1 is NOT set, 1 is missing
+      assert( has(6) );  // 2+4 is set because both are present
+      assert( !has(7) ); // 1+2+4 not set, 1 missing
+
+      assert( !hasAny(1) );// 1 is not set
+      assert( hasAny(2) ); // 2 is set
+      assert( hasAny(3) ); // 2 is set and part of 3=1+2
+      assert( hasAny(4) ); // 4 is set
+      assert( hasAny(5) ); // 4 is and is part of 5=1+4
+      assert( hasAny(6) ); // 2+4 is set
+      assert( hasAny(7) ); // 2+4 are part of 7
+      assert( !hasAny(8) );
+      assert( !hasAny(9) );
+    }
+
+  // Set a mixed flag
+  fl.set(3);
+  assert(fl.has(3));
+  assert(fl.has(7));
+  assert(fl.flags == 7);
+
+  // Unset a flag
+  fl.unset(2);
+  assert(fl.flags == 5);
+
+  // And again
+  fl.unset(2);
+  assert(fl.flags == 5);
+
+  // Set and unset it with set()
+  fl.set(2,true);
+  assert(fl.flags == 7);
+  fl.set(2,false);
+  assert(fl.flags == 5);
+
+  // Now try an enum
+  enum MF
+    {
+      A = 1,
+      B = 2,
+      AB = 3,
+      C = 4
+    }
+
+  Flags!(MF) mf;
+  mf.set(MF.A);
+  assert(mf.has(MF.A));
+  assert(!mf.has(MF.AB));
+  mf.set(MF.B, true);
+  assert(mf.has(MF.B));
+  assert(mf.has(MF.AB));
+  mf.unset(MF.B);
+  assert(mf.has(MF.A));
+  assert(!mf.has(MF.B));
+  assert(!mf.has(MF.AB));
+}