We learn if/else on our first programming day. Then we forget the else

TL;DR: Be explicit. Even with Else.

Problems

• Readability

• Cognitive Load

• Unforeseen conditions

• Fail Fast Principle violation

Solutions

1. Write the explicit else

Context

If we early return on an IF sentence we can omit the else part.

Afterward, we Remove the IF and use polymorphism.

That is when we miss the real cases.

Sample Code

Wrong

function carBrandImplicit(model) {
  if (model === 'A4') {
    return 'audi';
  }
  return 'Mercedes-Benz';
}

Right

function carBrandExplicit(model) {
  if (model === 'A4') {
    return 'audi';
  }
  if (model === 'AMG') {
    return 'Mercedes-Benz';
  }

  // Fail Fast
  throw new Exception('Model not found);
}

Detection

[X] Automatic

We can check syntax trees and parse them and warn for missing else.

We can also rewrite them and perform mutation testing.

Tags

• Conditionals

Conclusion

This kind of smell brings a lot of public debate, and hate.

We must exchange opinions and value each pros and cons.

Relations

Code Smell 102 - Arrow Code

Maxi Contieri ・ Nov 15 '21

#oop #javascript #cleancode #refactoring

Code Smell 36 - Switch/case/elseif/else/if statements

Maxi Contieri ・ Nov 28 '20

#oop #webdev #tutorial #codenewbie

More Info

Stop Using Implicit Else

When To Use Implicit Else

Fail Fast

Maxi Contieri ・ Dec 6 '20

#codenewbie #programming #webdev #oop

How to Get Rid of Annoying IFs Forever

Maxi Contieri ・ Nov 9 '20

#oop #programming #codenewbie #tutorial

Credits

Photo by Elena Mozhvilo on Unsplash

The biggest issue on software teams is making sure everyone understands what everyone else is doing.

Martin Fowler

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