Experience with Traits in the Xerox Star Workstation

The Xerox Star (8010) is an integrated office workstation. Its software is written in an object-oriented style. Often, different applications will impose slightly different requirements on nominally similar objects which they use. Customization of object definitions for different applications is achieved by attaching modifiers called traits to pre-existing object defintions. This paper describes the approach and recounts our experience with traits.