On How TypeScript Handles Variance
This lesson gives the theory of how TypeScript handles variance.
We'll cover the following...
Type system variances
TypeScript variances use the nomenclature of another language, which is confusing by nature. It’s not something you must master since the compiler will stop you from doing anything crazy.
However, it’s good to understand before having the compiler manage the complexity for us. Before getting started, let’s create some interfaces to examine how TypeScript handles (or doesn’t handle) covariant, contravariant, bivariant, ...