dont-repeat-yourself

Refactoring duplicated code involves extracting repeated blocks into parameterized, reusable functions. This centralizes logic, reduces maintenance overhead, and ensures changes only need to be made in a single location.

The DRY principle in software development is the practice of centralizing knowledge to eliminate the repetition of code, logic, and data. It aims to reduce maintenance overhead and prevent bugs caused by updating duplicated logic in multiple places.

You need to refactor duplicated validation logic when you find yourself copying and pasting code blocks to make minor changes across files. Extracting this logic into a reusable function prevents inconsistencies and simplifies future updates.

The best way to handle developer rationalizations for keeping duplicated code is to apply a structured refactoring protocol. This provides pressure resistance during development by offering clear strategies to extract and parameterize repeated code blocks.

The DRY principle addresses code, logic, data, and structural duplication. Identifying these different forms of repetition allows developers to apply targeted refactoring patterns and fully centralize software knowledge.