Checking for a boolean condition to return a boolean value is awkward

TL;DR: Don't return explicit booleans. Most boolean usages are code smells.

Problems

• Declarativeness

• Ninja Code

• Implementative solutions

Solutions

1. Return a boolean proposition instead of checking a negation.

2. Answer must be a business logic formula, not an algorithm.

Context

When dealing with boolean formulas, it is more readable to show a business boolean formula than introduce a negated IF clause.

Programmers tend to return accidental implementative solutions instead of real business rules.

Sample Code

Wrong

function canWeMoveOn() {
  if (work.hasPendingTasks())
    return false;
  else
    return true;
}

Right

function canWeMoveOn() {
  return !work.hasPendingTasks();
}

Detection

[X] Automatic

Based on syntax trees, we can safely refactor the code.

Tags

• Boolean

Conclusion

Beware of returning booleans.

After the return, you will need an If statement which is also a code smell.

Relations

Code Smell 115 - Return True

Maxi Contieri ・ Feb 20 '22

Code Smell 101 - Comparison Against Booleans

Maxi Contieri ・ Nov 11 '21

#webdev #beginners #programming #tutorial

Code Smell 24 - Boolean Coercions

Maxi Contieri ・ Nov 14 '20

#oop #tutorial #boolean #coercion

Code Smell 62 - Flag Variables

Maxi Contieri ・ Feb 8 '21

#programming #oop #webdev #tutorial

Code Smell 102 - Arrow Code

Maxi Contieri ・ Nov 15 '21

#oop #javascript #cleancode #refactoring

Code Smell 51 - Double Negatives

Maxi Contieri ・ Dec 24 '20

#codenewbie #tutorial #programming #oop

More Info

• How to Get Rid of Annoying Ifs Forever

Credits

Photo by Morgan Housel on Unsplash

Thanks to Nico K. for this suggestion.

It's not at all important to get it right the first time. It's vitally important to get it right the last time.

Andrew Hunt

Software Engineering Great Quotes

Maxi Contieri ・ Dec 28 '20

#codenewbie #programming #quotes #software

This article is part of the CodeSmell Series.

How to Find the Stinky parts of your Code

Maxi Contieri ・ May 21 '21

#codenewbie #tutorial #codequality #beginners