Sjoerd Visscher (@sjoerdvisscher.w3future.com)

"Five-Point Haskell": Total Depravity (and Defensive Typing) I have thought about distilling the principles by which I program Haskell, and how I’ve been able to steer long-lived projects over years of growth, refactorings, and changes in demands. I find myself coming back to a few distinct and helpful “points” (“doctrines”, if you may allow me to say) that have yet to lead me astray. With a new age of software development coming, what does it even mean to write good, robust, correct code? It is long overdue to clarify the mindset we use to define “good” coding principles. In this series, Five-Point Haskell, I’ll set out to establish a five-point framework for typed functional programming (and Haskell-derived) design that aims to produce code that is maintainable, correct, long-lasting, extensible, and beautiful to write and work with. We’ll reference real-world case studies with actual examples when we can, and also attempt to dispel thought-leader sound bites that have become all too popular on Twitter (“heresies”, so to speak). Let’s jump right into point 1: the doctrine of Total Depravity, and why Haskell is perfectly primed to make living with it as frictionless as possible. Total Depravity: If your code’s correctness depends on keeping complicated interconnected structure in your head, a devastating incident is not a matter of if but when.Therefore, delegate these concerns to tooling and a sufficiently powerful compiler, use types to guard against errors, and free yourself to only mentally track the actual important things. https://blog.jle.im/entry/five-point-haskell-part-1-total-depravity.html