A mapped type is a loop over keys that produces an object or tuple type and looks as follows: {[PropKey in PropKeyUnion]: PropValue} In this blog post, we examine how mapped types work and see examples of using them. Their most importing use cases are transforming objects and mapping tuples.| 2ality.com
In this blog post, we explore how we can test that complicated TypeScript types work as expected. To do that, we need assertions at the type level and other tools.| 2ality.com