# Code Smell 09 - Dead Code

*Code that is no longer used or needed.*

TL;DR: Do not keep code "just in case I need it".

# Problems

- Maintainability

# Solutions

- Remove the code
- [KISS](https://en.wikipedia.org/wiki/KISS_principle)

# Examples

- Gold plating code or [Yagni](https://en.wikipedia.org/wiki/You_aren%27t_gonna_need_it) code.

# Exceptions

- Avoid metaprogramming. When used, it is very difficult to find references to the code.

%[https://maximilianocontieri.com/laziness-i-meta-programming]

# Sample Code

## Wrong

[Gist Url]: # (https://gist.github.com/mcsee/9e793df7489a96dc27d29d0f4e963bdf)
```javascript
class Robot {   
  walk(){
    //...
    }
  serialize(){
    //..  
  }
  persistOnDatabase(database){
    //..  
  }
}

```

## Right

[Gist Url]: # (https://gist.github.com/mcsee/e1075cc971b5f7af28e37d29b492735d)
```javascript
class Robot {   
  walk(){
    //...
    }  
}
```

# Detection

Coverage tools can find dead code (uncovered) if you have a great suite of tests.

# Tags

- Unnecessary

# Conclusion

Remove dead code for simplicity.
If you are uncertain of your code, you can temporarily disable it using [Feature Toggle](https://en.wikipedia.org/wiki/Feature_toggle).
Removing code is always more rewarding than adding.

# More info

- [Laziness I: Metaprogramming](https://maximilianocontieri.com/laziness-i-meta-programming)

# Credits

Photo by <a href="https://pixabay.com/es/users/ray_shrewsberry-7673058/">Ray Shrewsberry</a> on <a href="https://pixabay.com/">Pixabay</a>

* * *

This article is part of the CodeSmell Series.

%[https://maximilianocontieri.com/how-to-find-the-stinky-parts-of-your-code]

*Last update: 2021/06/11*