Why use chained prototype inheritance in javascript?

Question

perf

Why do we build a prototype inheritance chain rather then using object composition. Looking up through the prototype for each step in the chain get\'s expensive.

Answer 1

Well, consider what would happen if lower or upper changed. The combined prototype wouldn't reflect that change since you've created a new object by copying properties from them.

For many situations that would be fine, but it's sure not as dynamic as actually constructing proper prototype chains for your objects.