CSCv2 | Version 2 of my Crazy Small CPU | Game Engine library

The logger decorator prints out to the console because the function is being evaluated. The return console.log(``class name ${name}``); line gets evaluated. The decorators are a bit different from the Angular ones because Angular uses the reflect-metadata package for doing a reflection kind of thing.

The error you are getting is because you have declared an interface and are trying to use it as if it had been initialised. In TypeScript, when you define an interface, it is only used for TypeScript to figure out the types on an object. When the TypeScript gets compiled, interfaces don't get outputted.

The reason that when you look at the definition for the Component decorator in Angular is an interface is because they are purposefully hiding the implementation details from you. They call it a Facade. They don't want you to actually navigate to the code for it, rather, they want you to see what the "Shape"* of the Component object is.

This is usually a type definition file .d.ts that will tell TypeScript what the types are for everything in Angular.

*"Shape" just refers to what the object is comprised of (methods, properties, etc.)