Stop the Return Roller-coaster
TL;DR: Prevent chaining return statements for better code readability and flow.
Problems
- Confusing flow
- Debugging Difficulty
- Buried logic
- Low readability
- Risk of errors
- Overuse of IF Sentences
Solutions
- Early return
- Clear conditions
- Use guard clauses
- Replace IFs with Polymorphism
Refactorings
Context
When you chain multiple return statements within a function, you create a confusing flow.
This leads to spaghetti code where understanding the exit points becomes hard.
Cascaded returns can hide important logic deep within the function, making it harder to follow and debug.
You read through multiple branches to determine when and where the function ends.
Sample Code
Wrong
function discount(price, isMember) {
if (price < 20) {
if (isMember) {
return 5;
} else {
return 2;
}
} else {
if (isMember) {
return 10;
} else {
return 0;
}
}
}
Right
class Member {
discount(price) {
return price < 20 ? 5 : 10;
// This ternary is an essential IF
// And you should NOT remove it
}
}
class NonMember {
discount(price) {
return price < 20 ? 2 : 0;
// This ternary is an essential IF
// And you should NOT remove it
}
}
function discount(price, status) {
return status.discount(price);
}
const member = new Member();
const nonMember = new NonMember();
Detection
[X] Automatic
You can spot cascaded returns by looking for multiple nested return statements.
If you see deep indentation or many layers of conditions, that's a sign of this code smell.
Tags
- IFs
Level
[X ] Beginner
AI Generation
AI generators might create this smell when tasked with solving complex problems quickly.
Cascaded returns often happen when the generator handles multiple conditions without optimizing the flow.
AI Detection
With clear instructions, AI tools can avoid cascaded returns.
You can ask the AI to use guard clauses, polymorphism and simplify returns for a cleaner solution.
Try Them!
Remember: AI Assistants make lots of mistakes
Without Proper Instructions | With Specific Instructions |
---|---|
ChatGPT | ChatGPT |
Claude | Claude |
Perplexity | Perplexity |
Copilot | Copilot |
Gemini | Gemini |
Conclusion
Avoid cascaded returns to make your code more readable, maintainable, and easier to debug.
Stick to early returns and guard clauses to prevent unnecessary complexity.
Relations
Code Smell 156 - Implicit Else
Maxi Contieri ・ Aug 6 '22
More Info
How to Get Rid of Annoying IFs Forever
Maxi Contieri ・ Nov 9 '20
Disclaimer
Code Smells are my opinion.
Credits
Photo by Mike Lewis HeadSmart Media on Unsplash
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Maxi Contieri ・ Dec 28 '20
This article is part of the CodeSmell Series.
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