How to specify coverbin for all negative integers

Coverage
1

I want to write a coverpoint for an integer x with 3 bins: zero, all positive values, and all negative values. Intuitively, I think the answer is as follows:

int x;

x_cp : coverpoint x {
    bins positive = {[1:$]};
    bins zero = {0};
    bins negative = {[$:-1]};
}

I cannot find any documentation in the SV language spec or online to confirm this intuitive solution is in fact correct. Is that negative bin covering negative -(2^31) to -1, or is it covering 1 to (2^31)-1. More than an answer, I am looking for a section in the SV language spec that I can read to understand .

2

Section 19.5.1 Specifying bins for values 19.5.1 Specifying bins for values says to reference section 11.4.13 Set membership operator in the IEEE 1800-2023 SystemVerilog LRM. There it says $ has the lowest or highest value based on the type of the expression. Section 19.5.7 Value resolution say the bin expression has the type of the coverpoint expression.