Refactoring Patterns: Operations & Techniques

A focused guide to the seven most impactful refactoring operations. Unlike code bloaters (which are smells to avoid), these are techniques you actively apply to improve design, clarity, and maintainability.

Pattern #1: Extract Method / Extract Function

What It Is

Pull out a section of code into a separate, named method/function. This is the most frequent refactoring operation.

When to Use

• Code section has a clear, single purpose but is buried in a larger method
• Same logic appears in multiple places (extract once, reuse everywhere)
• Method has complex local variables and you want to isolate them
• You want to test a section in isolation
• Code comment describes what a section does — that's a candidate for extraction