Status: IN
Singleton serves as enabling infrastructure across all three GoF categories: structurally (Facade often implemented as Singleton for subsystem access), behaviorally (State subclasses shared as Singletons for memory efficiency, ChangeManager as Singleton Mediator for update coordination), establishing Singleton as a cross-cutting infrastructure mechanism beyond its creational classification.
Three independent Singleton uses across Structural and Behavioral categories demonstrate Singleton transcends its Creational classification
Depends on (SL): facade-often-singleton, gof-changemanager-mediator-singleton, gof-state-subclasses-often-singletons