Object observation with Proxies

A Proxy wraps an object to intercept core operations like reads, writes, and key lookups. Combined with Reflect, it powers modern reactive frameworks.

Worked example

How it reads

new Proxy(target, handler) creates an interceptor shell
get(obj, prop) intercepts property lookups on the target object

Cloud tip: Always return Reflect.get(...) inside proxies when forwarding original behavior to target objects.

index.js

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YOUR TURN

Make the set trap refuse negative values: log rejected -5 and return true without storing it. Try obs.stars = -5, then log stats.stars (20).

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