Deco

The standard TS typing of this is: ```ts type T = { a: string; } | { b: string; } ``` One way to achieve this type in Runtypes is:...

Runtypes is pure by design. It doesn't modify the value. It only performs validation. If you like Runtypes, check out [Funtypes](https://github.com/ForbesLindesay/funtypes) Personally, I have started replacing my usage of Runtypes...

I can confirm this for TypeScript 4.9.3 on Yarn 3.3.0 with `nodeLinker: node-modules`. I tried both `yarn patch typescript@npm:4.9.3` and `yarn patch "typescript@patch:typescript@npm%3A4.9.3#~builtin::version=4.9.3&hash=d73830"`. Neither would successfully commit.