A method and system for dynamically processing instance data are provided. A namespace manager obtains declarative language instance data including tags, attributes and values for generating user interface objects. The instance data refers to one or more modules registered with a namespace manager in which the modules include meta-data defining one or more class definitions in a class hierarchy. Each class definition defines one or more properties of the class and references to a superclass/subclass(es) for the class. Thereafter, the namespace manager validates the instance data according to the class hierarchy and generates object code for instantiating an object hierarchy having classes, properties and values corresponding to the instance data.