4 files changed, 10 insertions, 11 deletions
diff --git a/src/core/RangeSet.cpp b/src/core/RangeSet.cpp
index c07dc9b..72953b0 100644
--- a/src/core/RangeSet.cpp
+++ b/src/core/RangeSet.cpp
@@ -20,13 +20,11 @@
 
 namespace ousia {
 
-static Cardinality createAny()
+Cardinality Cardinality::any()
 {
 	Cardinality any;
-	any.merge(Range<size_t>::typeRangeFrom(0));
+	any.merge(Range<size_t>::typeRange());
 	return std::move(any);
 }
-
-const Cardinality AnyCardinality = createAny();
 }
 
diff --git a/src/core/RangeSet.hpp b/src/core/RangeSet.hpp
index f5b56e2..9310d72 100644
--- a/src/core/RangeSet.hpp
+++ b/src/core/RangeSet.hpp
@@ -417,9 +417,10 @@ public:
 /**
  * This is the default cardinality.
  */
-using Cardinality = RangeSet<size_t>;
-extern const Cardinality AnyCardinality;
-
+class Cardinality : public RangeSet<size_t> {
+public:
+	static Cardinality any();
+};
 }
 
 #endif /* _OUSIA_RANGE_SET_HPP_ */
diff --git a/src/core/model/Domain.cpp b/src/core/model/Domain.cpp
index 3284759..7d5a76e 100644
--- a/src/core/model/Domain.cpp
+++ b/src/core/model/Domain.cpp
@@ -320,7 +320,7 @@ StructuredClass::StructuredClass(Manager &mgr, std::string name,
                                  Handle<StructuredClass> superclass,
                                  bool transparent, bool root)
     : Descriptor(mgr, std::move(name), domain),
-      cardinality(std::move(cardinality)),
+      cardinality(cardinality),
       superclass(acquire(superclass)),
       subclasses(this),
       transparent(transparent),
@@ -533,7 +533,7 @@ Rooted<StructuredClass> Domain::createStructuredClass(
     bool transparent, bool root)
 {
 	return Rooted<StructuredClass>{new StructuredClass(
-	    getManager(), std::move(name), this, std::move(cardinality), superclass,
+	    getManager(), std::move(name), this, cardinality, superclass,
 	    std::move(transparent), std::move(root))};
 }
 
diff --git a/src/core/model/Domain.hpp b/src/core/model/Domain.hpp
index cd05441..53579bd 100644
--- a/src/core/model/Domain.hpp
+++ b/src/core/model/Domain.hpp
@@ -751,7 +751,7 @@ public:
 	 */
 	StructuredClass(Manager &mgr, std::string name,
 	                Handle<Domain> domain = nullptr,
-	                Variant cardinality = AnyCardinality,
+	                Variant cardinality = Cardinality::any(),
 	                Handle<StructuredClass> superclass = nullptr,
 	                bool transparent = false, bool root = false);
 
@@ -1010,7 +1010,7 @@ public:
 	 * @return                     the newly created StructuredClass.
 	 */
 	Rooted<StructuredClass> createStructuredClass(
-	    std::string name, Variant cardinality = AnyCardinality,
+	    std::string name, Variant cardinality = Cardinality::any(),
 	    Handle<StructuredClass> superclass = nullptr, bool transparent = false,
 	    bool root = false);