Possible Worlds Versioning

Abstract

We present a history of the application of the possible-world semantics of intensional logic to the development of versioned structures, ranging from simple software configuration to the networking of distributed contextaware applications permeated by multiple shared contexts.In this approach, all of the components of a system vary over a uniform multidimensional version, or context, space, and the version tag of a built version is the least upper bound of the version tags of the selected bestfit components. Context deltas allow the description of changes to contexts, and the subsequent changes to components and systems from one context to another. With aethers, active contexts with multiple participants, several networked programs may communicate by broadcasting deltas through a shared context to which they are continually adapting.