Clik here to view.
Refactoring and Programming Language Semantics
Refactoring improves the design of code without changing its observable behavior. But what is observable behavior? We’ll look at how language semantics affect that. When you devise new refactorings,...
View ArticleLoop Unrolling: While ⇒ If-While
Loop unrolling is a performance optimization where you repeat the inside of a loop to reduce the looping overhead. It’s also a way to get rid of loops, and we’ll look at an example from a test. While...
View ArticleClik here to view.
2021 Articles in Review
Here are the the articles and videos I made last year. Key topics: user stories, refactoring, TDD, functional languages, and design. I’ve grouped them into these areas: User...
View ArticleRefactoring, a Whole-Team Guide
A one-page summary of Refactoring is available in PDF. Refactoring is…? Changing the design of existing code without changing its observable behavior (per Martin Fowler). These changes include...
View ArticleClik here to view.
Refactoring: Replace Method with Method Object
Sometimes, when you try to break up a long method, you run into a problem: you have to pass a bunch of local variables into the new method, some of which are both input and output. One solution is the...
View ArticleClik here to view.
Refactoring: Extract Local Lambda
Extracting a local lambda turns a block of code into an anonymous inline function. Motivation A local lambda can isolate code for improvement (the Isolate-Improve-Inline pattern – see References), or...
View ArticleClik here to view.
Refactoring Undifferentiated Exceptions
Some exception-handling code peels apart exceptions to figure out how to handle them. This is a missed opportunity for more direct code. The Simple Case: Type-Tested Exceptions Sometimes we see...
View ArticleClik here to view.
Reduce Dependencies Using Lambda
When A depends on B (A → B), a change in B may force A to change as well. Dependencies are both good and bad: they let objects work together, but they make software harder to change. We can use lambda...
View ArticleRefactor: Inline-Adjust-Extract
Sometimes, we feel that something we extracted isn’t as good as it could be. The Inline-Adjust-Extract refactoring pattern can help fix that. It has three steps: Inline: put the extracted code back...
View ArticleTDD with a Function Pipeline
Our “geek” group tackled a problem a couple weeks ago, that one of us had heard suggested by Michael Feathers: given a sequence of numbers, tell how many non-zero runs it has. Ron Jeffries described a...
View Article