Type Driven Development (TDD). I was not mistaken: Type, not Test.

Question

Who can explain this approach with simple words to me?
Pros and cons? Examples?
Can I use this development approach with JavaScript?

Answer 1

https://blog.ploeh.dk/2015/08/10/type-driven-development/

Answer 2

In short. You begin writing your types first. These types are also a kind of programs (in Idris it uses the same syntax). Then you start coding and "run" these types to see if the code is doing what it's supposed to do. A type deliverers the input and checks the output in an automated fashion. Every time you start creating extra types before coding. During this procedure you can still test if the type still does what it did before. It is mostly a form of describing types. What a type is and what it can transfer and transform into. Like translate a byte to a character or a string (which is an array of characters).