# Code Smell 41 - Regular Expression Abusers

*RegEx are a wonderful tool, we should to use them carefully and not to look smart.*

# Problems

- Readability

- Maintainability

- Testability

- Intention Revealing

# Solutions

1. Use regular expression just for string validation. 

2. If you need to manipulate objects, don't make them strings. 

# Sample Code

## Wrong

%[https://gist.github.com/mcsee/d0e8d1c002a12a9f535ab2fef4440d31] 

## Right

%[https://gist.github.com/mcsee/f3df119d3be0cdfee7fddd6d725f92be] 

# Detection

Regular expressions are a valid tool.
There's not much automated way of checking for possible abusers. A whitelist might be of help.
 
# Tags

- Primitive Obsession

- Abusers

# Conclusion

Regular expressions are a great tool for string validation. We must use them in a declarative way and just for strings.

Names are very important to understand pattern meanings.

If we need to manipulate objects or hierarchies, we should do it in an *object way*.

Unless we have a conclusive benchmark of **impressive** performance improvement.  
 
# Relations

%[https://maximilianocontieri.com/code-smell-06-too-clever-programmer]

%[https://maximilianocontieri.com/code-smell-20-premature-optimization] 

# More info

%[https://maximilianocontieri.com/what-exactly-is-a-name-part-i-the-quest]

# Credits

Photo by <a href="https://unsplash.com/@john_jennings">John Jennings</a> on <a href="https://unsplash.com/s/photos/letters">Unsplash</a>

* * *

> A Perl program is correct if it gets the job done before your boss fires you. 

_Larry Wall_
 
%[https://mcsee.hashnode.dev/software-engineering-great-quotes]

* * *

This article is part of the CodeSmell Series.

%[https://mcsee.hashnode.dev/how-to-find-the-stinky-parts-of-your-code]