Instruction: Explain the concept of proxies in JavaScript and provide examples of their use cases.
Context: This question assesses the candidate's familiarity with ES6 features and their ability to manipulate object behavior.
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To get started, let's clarify what a proxy is in JavaScript. At its core, a proxy allows you to create a wrapper for an original object. This wrapper then intercepts and redefines the behavior of various operations performed on the original object. You can think of it as having a middleman that can control access and modify the behavior of interacting with a particular object.
For example, let's say we have an object representing a user, and we want to log every time a property is accessed. We can achieve this by using a proxy. We would create a proxy that wraps the original user object, and in the handler object, we provide a 'get' trap that logs the access before...