Why Can a Function Remember a Variable That Should Be Long Gone?

📰 Medium · Programming

Learn how JavaScript functions can remember variables even after their execution context is cleaned up, and understand the concept of closures

intermediate Published 27 Apr 2026

Action Steps

Define a function inside another function to create a closure
Use the inner function to access variables from the outer function's scope
Test the closure by calling the inner function outside of the outer function's execution context
Apply closures to real-world problems, such as creating private variables or functions
Compare the use of closures with other programming concepts, such as classes or modules

Who Needs to Know This

Developers working with JavaScript will benefit from understanding closures, as it can help them write more efficient and effective code

Key Insight

💡 Closures allow functions to access variables from their outer scope, even after the outer function has returned

Key Takeaways

Learn how JavaScript functions can remember variables even after their execution context is cleaned up, and understand the concept of closures

Full Article

Title: Why Can a Function Remember a Variable That Should Be Long Gone?

URL Source: https://medium.com/@gize.bonilla/why-can-a-function-remember-a-variable-that-should-be-long-gone-35f4192fc25d?source=rss------programming-5

Published Time: 2026-04-27T03:12:21Z

Markdown Content:
# Why Can a Function Remember a Variable That Should Be Long Gone? | by Gize Bonilla | Apr, 2026 | Medium

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# Why Can a Function Remember a Variable That Should Be Long Gone?

## Closures are the payoff of everything this series has built so far. They are not advanced magic — they are the natural result of how JavaScript handles scope

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A function runs and returns. Its execution context is cleaned up, its variables released, its room demolished. And then, somewhere else in your code, later, another function uses one of those variables. The room is gone. The variable is not. If you have ever wondered how that is possible, this is the episode the series was building to

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