lib/spread2rdf/namespace.rb in spread2rdf-0.0.1pre.1 vs lib/spread2rdf/namespace.rb in spread2rdf-0.0.1

@@ -1,7 +1,11 @@
 module Spread2RDF
   module Namespace
+    DEFAULTS = {
+        UNIT: ::RDF::Vocabulary.new('http://qudt.org/vocab/unit#')
+    }
+
     class << self
       def [](name)
         name = name.to_sym
         self.namespace[name] ||
             ( RDF.const_defined?(name) && RDF.const_get(name)) ||
@@ -16,11 +20,11 @@
           else raise ArgumentError, "expecting a namespace but got #{namespace}:#{namespace.class}"
         end
       end
 
       def namespace
-        @namespace ||= {}
+        @namespace ||= DEFAULTS
       end
 
       def namespaces
         namespace.values
       end
@@ -30,10 +34,10 @@
           when Symbol
             Namespace[namespace_descriptor]
           when RDF::Vocabulary, RDF::URI, String
             namespace_descriptor.to_s
           else
-            raise "invalid namespace: #{namespace_descriptor.inspect}"
+            raise "invalid namespace: #{namespace_descriptor.inspect}:#{namespace_descriptor.class}"
         end
       end
 
       def const_missing(name)
         self[name] or super