UCW

Meta Components 

Widget 

Simple Window 

Template 

(defgeneric template-component-environment (component)
  (:documentation "Create the TAL environment for rendering COMPONENT's template.

Methods defined on this generic function must return a TAL
environment: a list of TAL binding sets (see the documentation
for YACLML:MAKE-STANDARD-ENVIRONMENT for details on TAL
environments.)")
  (:method-combination nconc))
(defcomponent simple-template-component (template-component)
  ((environment :initarg :environment :initform nil)))

Container 

(defaction switch-component ((container container) label)
  (ensure-valid-component-label container label)
  (setf (container.current-component-name container) label))