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Everything You Need to Know About Closures and Memoization in JavaScript
JavaScript closures are an important concept that are used extensively in modern web development. In simple terms, closures allow a function to remember and access its lexical environment, even when that function is executed outside of its original scope. This concept may sound complicated at first, but it is an essential tool for creating modular, efficient, and secure code. In this post, we will explore closures in-depth and provide real-world examples of their usage.
What are Closures?
A closure is a function that has access to variables in its outer (enclosing) lexical environment. In other words, it can access variables and parameters defined in its parent function, even after that function has finished executing. This is made possible because of the way JavaScript handles scope.
In JavaScript, each function creates a new lexical scope. This means that any variables declared within a function are only accessible within that function’s scope. However, when a function is defined inside another function, the inner function has access to the outer function’s scope, including any variables or parameters defined within it. This is what makes closures possible.
