Primitives for programming multi-user interfaces
Prasun Dewan, Rajiv Choudhary · 1991
We have designed a set of primitives for programming multi-user interfaces by extending a set of existing high- level primitives for programming single-user interfaces.These primitives support both collaboration-transparent and collaboration-aware multi-user programs and allow existing single-user programs to be incrementally changed to corresponding multi-user programs, The collaborationaware primitives include primitives for tailoring the input and output to a user, authenticating users, executing code in a user's environment and querying and setting properties of it, and tailoring the user interface coupling.We have identified several application-independent user groups that arise in a collaborative setting and allow the original single-user calls to be targeted at these groups.In addition, we provide primitives for defining application-specific groups.Our preliminary experience with these primitives shows that they can be used to easily implement collaborative tasks of a wide range of applications including message systems, multi-user editors, computer conferencing systems, and coordination systems.In this paper, we motivate, describe, and illustrate these primitives, discuss how primitives similar to them can be offered by a variety of user interface tools, and point out future directions for work.