Instruction: Provide examples to highlight when and why you would use one over the other.
Context: This question assesses the candidate's deep understanding of TypeScript's type system, particularly the nuances and appropriate use-cases of interfaces and type aliases.
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Interfaces in TypeScript are used to define the shape of an object or a class. They can be extended and implemented, which makes them a great tool for declaring the structure of objects and for enforcing contract agreements within your code base. One of the strengths of interfaces is their ability to be merged. This means if you declare an interface twice with the same name, TypeScript will treat it as a single interface with the combined properties of both declarations. This feature is particularly useful in situations where you might be gradually expanding the properties of an object throughout your application or when you are working with large, complex objects that are spread across different files.
For example, suppose we're developing a feature for a social media application that involves a user profile. We might start with a basic UserProfile interface:...