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Code Smell 274 - Cascaded Returnsby@mcsee
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Code Smell 274 - Cascaded Returns

by Maximiliano ContieriOctober 10th, 2024
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Prevent chaining return statements for better code readability and flow.
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Maximiliano Contieri HackerNoon profile picture

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

  1. Early return
  2. Clear conditions
  3. Use guard clauses
  4. 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

https://hackernoon.com/how-to-find-the-stinky-parts-of-your-code-part-xxiv

https://hackernoon.com/how-to-find-the-stinky-parts-of-your-code-part-xxi

https://hackernoon.com/how-to-find-the-stinky-parts-of-your-code-part-xvi

https://hackernoon.com/how-to-find-the-stinky-parts-of-your-code-part-xxxii

More Info

Disclaimer

Code Smells are my opinion.

Credits

Photo by Mike Lewis HeadSmart Media on Unsplash


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Adam Tornhill


This article is part of the CodeSmell Series.