It’s tempting to use mutable state in your algorithm. It’s so convenient! And we’re so used to it, if we come from an imperative paradigm. But we must remember that there is always a way, even if it’s not immediately obvious. I go over two ways to implement an algorithm without mutable state.
Thoughts on Functional Programming Podcast
An off-the-cuff stream of Functional Programming ideas, skills, patterns, and news from Functional Programming expert Eric Normand.
What is the universal process pattern?
Part 3 of the functional architecture series. The universal process pattern is a schematic representation of software. For a software process to be useful, it needs input, it needs to calculate something from that input, and it needs to have some output or effect on the world.
What is the onion architecture?
Part 2 of the functional architecture series. When we’re structuring our functional software, we want to isolate the actions from the calculations. We can do that using the Onion Architecture, which has layers like an onion. The center of the onion is your domain model, then around that are your business rules. Finally, around that is your interaction layer, which talks with the outside world, including the database, web requests, api endpoints, and the UI.
More about Stratified Design
Part 1 in the Functional architecture series. The Stratified Design, which I called “layered design” before, is a way of architecting your code as a series of layers of meaning. It’s a common way of organizing your code and structuring your application.
Why is functional programming gaining traction? Why now?
The biggest companies in the world are investing heavily in functional programming. From Facebook building React and Reason, to Apple pivoting to Swift, to Google developing MapReduce, functional programming is gaining traction. But why? I go over four hypotheses and evaluate them.
Some thoughts on map, filter, and reduce
Are map, filter, and reduce popular for a reason? Do these things capture some essence of iteration? Are they just better for loops?
What do functional programmers think of the class inheritance hierarchy?
When a functional programmers looks at the typical OOP examples that show the inheritance hierarchy, they see something weird: why is one possible field plucked out to become the class? And why make it static?
Why do functional programmers focus on time?
It turns out that in distributed and parallel systems, time plays a huge role. I think that’s why fp is booming these days: all web sites are distributed systems. And web developers are facing all the irreducible problems of distributed systems, and they’re turning to fp for answers.
What is “to reify” in software?
“To reify” means “to make real”. It’s an old concept from philosophy. When you name a concept, you can start talking about it. We do something similar in programming. When you take a concept and make it first class, you can begin to manipulate it with the normal programming constructs.