For TypeScript 3.1, any function declaration or const declaration initialized with a function results in the type-checker analyzing the containing scope to track properties that get added.

Using generics in TypeScript is very similar to using them in, for example, C#. This method calls a generic function, specifying the data type to be used (string, in this case): res = ...

When classes are more structure than you need, tuples let you specify simple type-safe aggregates of other data types. They'll also let you create a dictionary collection…but it won't be type-safe. In ...