lib/mida/vocabulary.rb in mida-0.3.1 vs lib/mida/vocabulary.rb in mida-0.3.2

@@ -6,19 +6,15 @@
   # To specify a vocabulary use the following methods:
   # +itemtype+, +has_one+, +has_many+
   class Vocabulary
 
     class << self
-      # Return the properties specification
-      attr_reader :properties
-
       # Return the registered vocabularies
       attr_reader :vocabularies
     end
 
     @vocabularies = Set.new
-    @properties = {}
 
     # Register a vocabulary that can be used when parsing,
     # later vocabularies are given precedence over earlier ones
     def self.register(vocabulary)
       @vocabularies << vocabulary
@@ -39,17 +35,43 @@
 
     def self.inherited(subclass)
       register(subclass)
     end
 
+    # Return the properties specification
+    def self.properties
+      @properties ||= {}
+    end
+
+    # Return the included vocabularies
+    def self.included_vocabularies
+      @included_vocabularies ||= Set.new
+    end
+
+    # Include the properties from the specified <tt>vocabularies</tt>.
+    # This is the correct way to inherit properties from another vocabulary,
+    # rather than subclassing.
+    def self.include_vocabulary(*vocabularies)
+      vocabularies.each do |vocabulary|
+        included_vocabularies.merge(vocabulary.included_vocabularies)
+        included_vocabularies << vocabulary
+        properties.merge!(vocabulary.properties)
+      end
+    end
+
+    # As per the standard <tt>kind_of?</tt>, but also checks to see if vocabulary has
+    # been included by self
+    def self.kind_of?(vocabulary)
+      return true if self == vocabulary
+      return true if self.ancestors.include?(vocabulary)
+      included_vocabularies.include?(vocabulary)
+    end
+
     # Sets the regular expression to match against the +itemtype+
     # or returns the current regular expression
-    def self.itemtype(regexp_arg=nil)
-      if regexp_arg
-        @itemtype = regexp_arg
-      else
-        @itemtype
-      end
+    def self.itemtype(regexp=nil)
+      return @itemtype unless regexp
+      @itemtype = regexp
     end
 
 
     # Defines the properties as only containing one value
     # If want to say any property name, then use +:any+ as a name