def base
      base = Base.new

      type = @parser.graph.fetch("og:type", "website").downcase

      validate_type type

      @parser.graph.each do |property|
        build_property base, property
      end

      synthesize_required_properties base
      drop_empty_children base
      validate base

      base
    end
def base
      base = Base.new

      type = @parser.graph.fetch("og:type", "website").downcase

      validate_type type

      @parser.graph.each do |property|
        build_property base, property
      end

      synthesize_required_properties base
      drop_empty_children base
      validate base

      base
    end
Create a new builder.

 @param [Parser] parser
 @see Parser#graph
 @see Parser#additional_namespaces
 Build and return the base.

 @return [Base]