With TypeScript you can either specify types explicitly or let the compiler infer them.
Is there a way to add the types that are inferred to the original source code?
Eg I would start with:
private posX = 0;
private posY = 0;
private sizeX = 0;
private sizeY = 0;
I would run type inference, and since the types can be inferred in that case I would get:
private posX: number = 0;
private posY: number = 0;
private sizeX: number = 0;
private sizeY: number = 0;
This way when editing the code I could check if the inference worked as I expect, and I could manually provide more restrictive types if appropriate.
Someone actually implemented this!