How do closures interact with this in JavaScript?
Regular functions do not capture this in a closure; this is determined at call time. Arrow functions capture this lexically from the enclosing scope, so an arrow inside a method preserves the method's this. This is why arrows fix the this-in-callback bug.
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More FAQs in Closures Deep Dive: Interview Questions in JavaScript
Create a cache object in the outer function. Return a function that serializes the arguments as a key, checks the cache, and either returns the cached result or calls the original function and stores the result. The cache is private to the closure.
Close over a timer variable. Each call clears the previous timer and sets a new one. The function only runs after the user stops calling for the specified delay. The timer persists across calls via the closure.
No. Destructuring methods from a closure-based object (const { increment, getCount } = c) still close over the same private variables. Both increment and getCount access the same count. The closure is not broken.
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