Exploring Extreme Programming
Exceptions are one of the most complicated constructs in many languages. Because of that, testing exceptions is one of the harder tests to do. Consider the following code. Assume block1 through block3 are straight-line code, each ending with a statement Continue reading Testing Exceptions: Harder Than It Looks
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 renaming, reducing duplication, rearranging code, and more. Even large refactorings are built Continue reading Refactoring, a Whole-Team Guide
Exceptions are complicated, so it’s no surprise that they can be misused. A “smell” describes potential problems; whether it’s really a problem is your judgment. Let’s look at smells you may find with exceptions. Empty Exception Handlers Java has the Continue reading Code Smells in Exceptions
How should we handle error conditions? We’ll look at the try-catch exception mechanism that’s similar across many languages, and a few patterns and pitfalls for working with it. Old-School One way of handling errors is for a method to have Continue reading Spooky Action at a Distance: Exceptions
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: My favorites: Want More?Have you found these articles useful or want more? * Continue reading 2021 Articles in Review
Operating System Principles, by Per Brinch Hansen. 1973. This is a classic book on operating systems – better than many of its successors. What I love about this book is that it comes just after an era of experimentation, when Continue reading Review: Operating System Principles
Immutability is the idea that once created, data never changes. Why might we want this? Avoid aliasing bugs: Aliasing occurs when there are multiple ways to access the same piece of data, and one piece changes it in a way Continue reading Immutable Objects
Functional languages often have immutable data types – you can’t change an object once you’ve created it, though you can include it as part of other objects. Immutable objects are easier to reason about, and prevent errors where two parts Continue reading Queues from Stacks: Functional Data Types
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, you have to take semantics into account. The Simple View is Continue reading Refactoring and Programming Language Semantics
Coupling occurs when one part of a system depends on another part. That is, if one part changes, the other must be adjusted too. Lambda expressions can reduce coupling by needing to refer to fewer things. Dependencies on Objects Consider Continue reading Lambda to Reduce Coupling