This is a Typescript type-level computation (which is Turing-complete AFAIK). However this kind of trickery is usually done for fun and to explore how much could be achieved just on the compile step.

Something similar to VSCode’s ability to open searches in an editor? Looks like you can save and reopen them too.

LINQ looks great with the query syntax:

var productsByCategory =
    from p in dbContext.Products
    where p.Price < 50
    group by p.Category.Id
    select p;