Michael Feathers has a great blog post up today about how object-oriented and functional programming styles are suited to different portions of an application. Specifically, the object-oriented style fits the high-level application components. The original intention of OO was for objects to pass messages to each other, which is suited to a SOA style and …
This F# Snippet illustrates a way to divide a sequence into a sequence of shorter sequences of a fixed length. The snippet uses list comprehensions. I don’t like it, because it involves flipping through the original sequence over and over and over. With recursion, we can do all the construction in one pass through the …
John Backus (pdf) distinguishes two parts of a programming language: “First, its framework which gives the overall rules of the system, and second, its changeable parts, whose existence is anticipated by the framework but whose particular behaviour is not specified by it.” The framework part is all the built-in language constructs. The changeable parts are …
Gradle, the build system, is a DSL on top of Groovy. The build scripts (which are really configuration scripts) are Groovy code. So why do they look so weird? Today I configured a particular obscure property of the eclipse plugin in milestone 6 of Gradle. The answer looks like: apply plugin: ‘eclipse-wtp’eclipse { wtp { …
At work, we use dependency injection to build up small, decoupled classes each with a single responsibility. DI lets us assemble these in multiple different ways, so we can use the same class for similar processes. This strategy of combining small pieces of functionality in different ways is also a goal of functional programming. Let’s …
I’m currently distracted from life, immersed in Concepts of Modern Mathematics. Did you know that you can find out whether a number is prime by multiplying all the integers before it, adding one, and then dividing by the number of interest? Me neither! it’s like this: a number p is prime if and only if: …
Google’s guava library provides a few constructs that let us use functional style in Java. Personally, I enjoy the slightly more declarative style that results, and have a new game of eliminating loops. Unfortunately, it’s Java. Attempting to do anything functionally is rather ugly. What do you think – worth it? or unreadable? Before: public …