#pragma once is a de-facto standard now, and if it’s not in the actual standard then that says more about the failings of the standard writers than anything else.

And there’s absolutely no reason to typedef _standard_ int types anymore. Not in C, and definitely not in C++. That’s just crusty old practices. Maybe if you want to have nice short types like u8, i8, etc, I can understand that. But SlangUint32 is just ugly.