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JavaScript Closures vs. Anonymous Functions
In JavaScript, a closure occurs when an inner function has access to the outer scope's variables, even after the outer function has completed execution. Many functions in JavaScript are considered closures, but only a specific subset is of particular interest theoretically.
Case 1: Friend's Code
<code class="js">(function f() { var i2 = i; setTimeout(function g() { console.log(i2); }, 1000); })();</code>
Case 2: Your Code
<code class="js">setTimeout((function f(i2) { return function g() { console.log(i2); }; })(i), 1000);</code>
Conclusion
Therefore, in both the provided solutions, the inner function g is a closure, but not the outer ones. This demonstrates that although they achieve the same result, they do so through different mechanisms.
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