Ep 093: Waffle Cakes

Functional Design in Clojure

Each week, we discuss a different topic about Clojure and functional programming.

If you have a question or topic you'd like us to discuss, tweet @clojuredesign, send an email to [email protected], or join the #clojuredesign-podcast channel on the Clojurians Slack.

This week, the topic is: "effective composition." We search for that sweet spot between full-featured mixes and simple ingredients when crafting your software recipes.

Our discussion includes:

• What makes code "composable"? What makes it "not composable"?
• What baking has in common with software design.
• What baking does not have in common with software design.
• Are you using ingredients or a box mix?
• How to know when you need to split something apart.
• When is a part too big? When is a part too small?
• What is too flexible?
• The principle of orthogonality.
• Decomposing without the smell.

Selected quotes:

• "This is a Clojure podcast. We have to have a definition every once in a while."
• "When you try to take code that someone has made and combine it with other things, how much resistance, how much difficulty, do you begin to encounter?"
• "A cake is a composition of smaller things."
• "You're still composing a cake. You're just composing it out of bigger things."
• "Let's compose dinner together."
• "You might be fighting against some of the ingredients, because you have a whole lot of stuff that's been premixed that comes along for the ride."
• "What if you want waffles?"
• "Everything is made of atoms! If I could assemble atoms, I have ultimate flexibility!"
• "If it's narrowly focused, it's hard for it to get in the way of other things."
• "You're making well-suited things, that have small scopes of responsibility, so that you can weave them together appropriately for your domain."
• "Who owns the recipe?"
• "Ah yes, you are the cause and the solution of the problem!"
• "Are you able to write a new recipe and reuse all the ingredients?"

Links:

• Ep 033: Cake or Ice Cream? Yes!
• Ep 065: Stuck in the Middle
• Ep 079: Compose Thyself