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Clean code - avoiding IF nesting ✨

Jesús Mejías Leiva Updated on ・1 min read

Introduction

Today I come to share a little tip to improve the readability of our code. We will achieve this by using guard clauses which will help us avoid this `IF` nesting.

Examples

In this example, we can see how and `IF` nesting appears, in this case, it is a simple example but this can get complicated, with each nesting that is added the code will become less readable and therefore less friendly and less maintainable.

``````const calculatePercentageHeight = (width, height) => {
const result = (height * 100) / width;

if (!Number.isNaN(result)){
if (Number.isInteger(result)){
return result
}else{
return result.toFixed(2)
}
}else{
return 0
}
};

// use function
calculatePercentageHeight(50,50) // result 100
calculatePercentageHeight(50,0) // result 0
``````

Good ✅

Using guard clauses we avoid the nesting of `IF` conditionals since we will "first control the error cases", and then we will continue with our logic.

``````const calculatePercentageHeight = (width, height) => {
const result = (height * 100) / width;

if (Number.isNaN(result)) return 0; // guard clause
if (Number.isInteger(result)) return result; // guard clause

return result.toFixed(2);
};

// use function
calculatePercentageHeight(50,50) // result 100
calculatePercentageHeight(50,0) // result 0
``````

Conclusion

Using guard clauses is good practice to avoid unnecessary ramifications and therefore make your code easier and more readable. If we apply these guidelines we will make our software much more maintainable and friendly.