Status: IN
Visitor achieves two forms of structural independence that distinguish it among GoF behavioral patterns: it can operate on objects that do not share a common parent class, and it can traverse diverse object structures — composites, sets, lists, and directed acyclic graphs — including across unrelated class hierarchies.
Visitor's dual independence from type hierarchy and traversal substrate maximizes its applicability domain
Depends on (SL): gof-visitor-no-common-parent-required, visitor-traverses-any-object-structure