29 lines
849 B
Markdown
29 lines
849 B
Markdown
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---
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title: Avoid Mutations and Side Effects Using Functional Programming
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---
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## Avoid Mutations and Side Effects Using Functional Programming
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### Problem Explanation
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Fill in the code for the function `incrementer` so it returns the value of the global variable `fixedValue` increased by one. `fixedValue` should not change, no matter how many times the function `incrememter` is called.
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### Hint 1
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Using the increment operator (`++`) on `fixedValue` will mutate `fixedValue`, meaning it will no longer reference the same value it was assigned with.
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### Solution:
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```javascript
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// the global variable
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var fixedValue = 4;
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function incrementer () {
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// Add your code below this line
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return fixedValue + 1;
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// Add your code above this line
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}
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var newValue = incrementer(); // Should equal 5
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console.log(fixedValue); // Should print 4
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```
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