Traditionally, closures have been a feature of purely functional programming languages. JavaScript shows its affinity with such functional programming languages by considering closures integral to the core language constructs. Closures are gaining popularity in mainstream JavaScript libraries and advanced production code because they let you simplify complex operations. You will hear experienced JavaScript programmers talking almost reverently about closures—as if they are some magical construct far beyond the reach of the intellect that common men possess. However, this is not so. When you study this concept, you will find closures to be very obvious, almost matter-of-fact. Till you reach closure enlightenment, I suggest you read and ...

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