TypeScript: Gradual, Structural, Dynamic, Static.
TypeScript is probably one of the most unique programming languages in the world. Instead of defining language syntax and semantics on its own, it sits on top of JavaScript, which is used by millions! This brings us to one of TypeScript’s biggest use-cases: Being a way to formalise JavaScript’s most erratic behaviour. But how can a type-system grasp all the powerful flexibility of a programming language so inherently dynamic, without restricting JavaScript’s expressiveness a single bit? In this talk, we’re going to see how! We redefine types for a single function bit by bit, getting more type-safe with each step. Dynamic behaviour with static types. In the end, only JavaScript remains.
Talk takeaways
TypeScript is still JavaScript
Make use of gradually adopting stronger and more explicit types
Generic binding capabilities and conditionals allow for exact sub-typing
A dynamic language needs types that change depending on context
String template literal types are the missing piece for a flexible range of types
About Stefan
Stefan Baumgartner is a Software Architect at Dynatrace. He recently published "TypeScript in 50 Lessons" for Smashing Magazine and writes regularly on fettblog.eu. Next to writing, podcasting, organizing conferences and meet-ups, he also enjoys Italian food, Belgian beer, and British vinyl.