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The JavaScript Interview Handbook: 100+ Interview Questions

Solution Review: prototype.toString & "typeof"

Discover how JavaScript's prototype.toString method and typeof operator work with objects created by constructor functions. Learn the effects of invoking functions versus referencing them, and understand common pitfalls like automatic return of undefined due to line breaks in return statements. This lesson enhances your grasp of type coercion and validation in JavaScript.

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Question 1: Solution review #

Explanation #

Let’s understand what is happening in the following part of the code first:

new (function Custom() {}))

You can see that the function Custom is defined with an empty body. Since we ...