Disallow exports that are not valid C/C++ identifiers

[sbc100]

I use std.isdentifier() here from python since it has the same rules for valid identifiers are C/C++.

We could try instead to allow this but I'm not sure it worth it given that our inputs are almost exclusively compiled from C/C++/rust.

See #23560

[dschuff]

as I mentioned in #23560 it's actually JS identifier rules that matter here, not C; are they different?

[sbc100]

as I mentioned in #23560 it's actually JS identifier rules that matter here, not C; are they different?

JS identifier rules are a bit more relaxed. You can do $foo for example. I think we want to stick to the more strict C/C++ rules. I don't see any reason to allow anything else at this point.

[sbc100]

as I mentioned in #23560 it's actually JS identifier rules that matter here, not C; are they different?

JS identifier rules are a bit more relaxed. You can do $foo for example. I think we want to stick to the more strict C/C++ rules. I don't see any reason to allow anything else at this point.

We can always relax things later if had the need to.

[sbc100]

I propose that we land this and then consider expanding later.

[sbc100]

OK to land this?