Code Smell 65 - Variables Named after Types

Names should always indicate role.

25 March, 2023

Contributors

Maxi Contieri

@mcsee

Problems

Declarative
Design for Change
Coupling to accidental implementation

Solutions

Rename your variable according to the role.

Sample Code

Wrong

public bool CheckIfStringHas3To7LowercaseCharsFollowedBy3or4Numbers(string string)
{
  Regex regex = new Regex(@"[a-z]{2,7}[1-9]{3,4}")
  var hasMatch = regex.IsMatch(string);
  return hasMatch;
}

Right

public bool CheckIfStringHas3To7LowercaseharsFollowedBy3or4Numbers(string password)
{
  Regex stringHas3To7LowercaseCharsFollowedBy3or4Numbers = new Regex(@"[a-z]{2,7}[1-9]{3,4}")
  var hasMatch = stringHas3To7LowercaseCharsFollowedBy3or4Numbers.IsMatch(password);
  return hasMatch;  
}

Detection

This is a semantic rule. We can instruct our linters to warn us from using names related to existing classes, types o reserved words since they are too implementative.

Conclusion

The first name we can across is related to an accidental point of view. It takes time to build a theory on the models we are building using our MAPPERS. Once we get there, we must rename our variables-

Relations

Code Smell 38 - Abstract Names

More Info

https://maximilianocontieri.com/what-exactly-is-a-name-part-ii-rehab

http://xunitpatterns.com/Intent%20Revealing%20Name.html

Credits

Photo by Sangga Rima Roman Selia on Unsplash

This idea came from this tweet

https://twitter.com/1377522389312008193

Types are essentially assertions about a program. And I think it’s valuable to have things be as absolutely simple as possible, including not even saying what the types are.

Dan Ingalls

Software Engineering Great Quotes

This article is part of the CodeSmell Series.

How to Find the Stinky Parts of your Code