The appended script
doesn't generate any complaints about the non-sensical attributes; and the one attribute that does make sense, &default, doesn't work, this script generates an error complaining about a's value not being set.
I'd probably say even &default doesn't make sense to permit there? One probably would initialize a default value via = assignment instead?
You mean why use "global a: count &default = 5" instead of "global a = 5"? Yeah, I agree. There are maybe microcases where there's a semantic difference (like when assigning to an &optional record field), but that's about it.
Yeah, that's all I meant: &default doesn't seem useful in the case of of a global.