Invisible objects have rules we need to enforce in a single point

TL;DR: Create Small objects and restrict your domain.

Problems

• Bijection Fault

• Fail fast principle violation

• Repeated Code validation

Solutions

1. Create small objects and validate the domain.

Context

This is a primitive obsession smell.

EmailAddresses are a subset of string.

Valid Ages are a subset of Real.

Ports are a subset of Integers.

A wordle word is a subset of String.

Sample Code

Wrong

destination = "destination@example.com"

destination = "destination.example.com"
// No error thrown

Right

public class EmailAddress {
    public String emailAddress;

    public EmailAddress(String address) {
        string expressions = @"^\w+([-+.']\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*$";
        if (!Regex.IsMatch(email, expressions) {
          throw new Exception('Invalid address');
        }
        this.emailAddress = address;
    }
}

destination = new EmailAddress("destination@example.com");

Not to be confused with the anemic Java version

Detection

[X] Manual

This is a semantic smell.

Tags

• Primitive Obsession

Conclusion

We need to be loyal to the bijection of the real world.

Subsets are very important for early validations and fail fast principle.

Relations

Code Smell 122 - Primitive Obsession

Maxi Contieri ・ Mar 17 '22

#oop #webdev #tutorial #beginners

More Info

Fail Fast

Maxi Contieri ・ Dec 6 '20

#codenewbie #programming #webdev #oop

Disclaimer

Code Smells are just my opinion.

Credits

Photo by Mona Eendra on Unsplash

Every craftsman starts his or her journey with a basic set of good-quality tools.

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