A subclass that overrides several methods to implement variant behavior — `PremiumBooking extends Booking` overriding `charge()`, `discount()`, `notify()` with premium variants.
A subclass that overrides several methods to implement variant behavior; the agent reasoning about polymorphic dispatch must enumerate variants across the hierarchy.
Behavior that varied via inheritance now varies via a delegate object that implements the variant interface.
Variants live in delegate objects the host holds and forwards to; the agent reads one host class plus the held delegate's interface instead of climbing an inheritance chain to predict behavior.
Before the refactoring
class Booking { /* ... */ }class PremiumBooking extends Booking {/* overrides several methods */}
After the refactoring
class Booking {type; // 'standard' | premium delegatecharge() { return this.type.charge(this); }}
Behavior can't change at runtime; combining variants requires multiple inheritance; the inheritance relationship may violate Liskov in subtle ways.
Behavior can't change at runtime; combining variants requires multiple inheritance the agent must work around; Liskov violations hide in override behavior.
Composition is more verbose at construction sites — accept the verbosity in exchange for the flexibility.
Composition is more verbose at construction sites; the agent loses syntactic polymorphism and must verify behavior through explicit delegation calls.
Variants can be combined or swapped at runtime; Liskov violations vanish; the hierarchy tree flattens.
Behavior changes at runtime by swapping the delegate; the agent reasons against one host signature plus the delegate's interface, without loading the inheritance graph to verify which override applies to a given instance.
Replacing every subclass with composition — including ones where the inheritance contract genuinely holds — pays construction-site verbosity for no real fit improvement.
Replacing inheritance with delegation on hierarchies where every subclass honors the parent's contract adds construction-site setup and a forwarding method per parent method without changing what the agent's generated calls do.