Multiple return Code Flow Minefields

How multiple return statements in a single function may lead to undesirable behaviours.

Multiple return statements in a single function can make the code harder to understand, maintain, and predict, and should be avoided whenever possible. Here are a few reasons why:

1. Complexity: Functions with multiple return statements can be more difficult to understand, as you have to keep track of multiple exit points in the code. This can make it harder to follow the flow of the function and understand how it works.
2. Maintainability: Functions with multiple return statements can be harder to modify or extend, as you have to consider all of the different return points in the code. This can make it more time-consuming to make changes to the function, and can increase the risk of introducing bugs.
3. Readability: Functions with multiple return statements can be harder to read, as you have to keep track of multiple exit points in the code. This can make it more difficult to follow the logic of the function and understand what it does.
4. Predictability: Functions with multiple return statements can be harder to predict, as you have to consider all of the different conditions that can trigger a return statement. This can make it more difficult to understand and predict the behaviour of the function, and can increase the risk of introducing bugs.
5. Assumptions: It is important to consider that developers may not always read your entire code in detail when using it. In libraries and other reusable code, it is common for developers to make assumptions about the behavior of the code based on its naming, structure, and the most common use cases. Functions with multiple return statements can make it harder for developers to make these assumptions, as they have to consider all of the different conditions that can trigger a return statement. This can make it harder for developers to understand and use the code effectively and increase maintenance risks.

To avoid these problems, it is generally recommended to minimize the use of return statements and use them only when necessary. Instead of using multiple return statements, you can use control structures like if statements and for loops to control the flow of the function, and use a single return statement at the end of the function to return the final result.

Simplicity of Predictable Code Chains

Code that is written as a chain of called functions with a single return statement can be simpler and easier to understand, as it has a clear flow and a single exit point. This can make it easier to follow the logic of the code and understand how it works. Avoiding potential maintenance minefields of unpredictable flows.

Caveats

There are situations where it may be cleaner and simpler to use multiple return statements, even if it leads to multiple returns. This usually happens when multiple verification layers can be avoided by a simple entry-level early return statement. Or when the parameter verification is required for the function computation. In these cases, the use of multiple return statements can help to simplify the code and improve its readability.