closure

1-js/06-advanced-functions/03-closure/3-counter-independent/solution.md

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+The answer: **0,1.**
+
+Functions `counter` and `counter2` are created by different invocations of `makeCounter`.
+
+So they have independent outer Lexical Environments, each one has its own `count`.

1-js/06-advanced-functions/03-closure/3-counter-independent/task.md

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+importance: 5
+
+---
+
+# Are counters independent?
+
+Here we make two counters: `counter` and `counter2` using the same `makeCounter` function.
+
+Are they independent? What is the second counter going to show? `0,1` or `2,3` or something else?
+
+```js
+function makeCounter() {
+  let count = 0;
+
+  return function() {
+    return count++;
+  };
+}
+
+let counter = makeCounter();
+let counter2 = makeCounter();
+
+alert( counter() ); // 0
+alert( counter() ); // 1
+
+*!*
+alert( counter2() ); // ?
+alert( counter2() ); // ?
+*/!*
+```
+