Declarative Validation
In the past two years I’ve become reasonably comfortable with both PureScript and Haskell. I’ve learned so many new things while diving into the pure functional programming ecosystem and many of these techniques can be applied to other paradigms. Unfortunately, the pure FP world can feel a bit like another dimension – where many programming problems have elegant solutions but the world of “regular” programming isn’t aware of these patterns. One such pattern is called “applicative-style validation”, but I’ll simply call it “declarative validation”. In this post I’ll provide some motivation for using this technique and then build a small library in Python implementing these ideas. ...