Code Smell 46 — Repeated Code
DRY is our mantra. Teachers tell us to remove duplication. We need to go beyond.
- Code Duplication
- Don’t Repeat Yourself
- Find repeated patterns (not repeated code).
- Create an abstraction.
- Parametrize abstraction calls.
- Use composition and never inheritance.
- Unit test new abstraction.
Linters can find repeated code.
There are not very good finding similar patterns.
Maybe soon machine learning will help us find such abstractions automatically.
For now, it is up to us, humans.
Repeated code is always a smell.
Copying and pasting code is always a shame.
With our refactoring tools, we need to accept the duplication remove challenge trusting our tests as a safety net.
Code Smell 11 — Subclassification for Code Reuse
Code reuse is good. But subclassing generates a static coupling.
DRY - Don't repeat yourself
The DRY principle is an integral part of clean code, but what does it actually mean and what is it really good for…
Copy and paste is a design error.
This article is part of the CodeSmell Series.