Intensional Changes: Modularizing Crosscutting Features

Feature-oriented programming (FOP) targets the encapsu- lation of software building blocks as features which better match the specification of requirements. As a result, pro- grammers find it easier to design and compose different vari- ations of their systems. Change-based \{FOP\} \{(CFOP)\} pro- poses to specify features as sets of first-class change objects which can add, modify or delete building blocks to or from a software system. First, we show how \{CFOP\} supports the modularization of crosscutting functionality. Afterwards, we expose a weak- ness of \{CFOP\} which is a consequence from features holding extensional sets of changes. We elaborate on a solution for that weakness which is based on intensional changes: de- scriptions that can evaluate to an extension of changes.