📷 As a programmer, you want your code to be efficient, readable, cool, and easy to maintain. One way to achieve this is by using guard clauses and early return statements. These techniques can help you simplify your code and make it easier to follow. In this post, I’ll explore what guard clauses and early return statements are, and how they can help you write better code.
What are Guard Clauses?
A guard clause (or an early return statement) is a very simple technique to check for invalid input or edge cases at the beginning of a function, and return as soon as possible if an error is detected. This reduces the number of nested if statements and makes the code more readable.
Consider the following example, which checks if a number is positive:
def is_positive(number):
if number >= 0:
if number == 0:
return False
else:
return True
else:
return False
This code works fine, but it would look weird if more and more nested ifs are used. It can be simplified using a guard clause. Here’s the refactored version:
def is_positive(number):
if number < 0:
return False
if number == 0:
return False
return True
In this version, we check for the invalid case first and return as soon as possible. Therefore the rest of the code would not be executed. This makes the code more pleasant to look at, as the return statement provides a clear and explicit indication of the code flow.