Any possibility of considering a somewhat more numerically
consistent abstract notation for ambiguously signed values?

(i.e. ~nan.0 replaces the positively signed +nan.0 notation)

Thereby enabling the optionally supported designations:

~inf.0                                             ~inf.0
-inf.0                  -0.0 0 +0.0                +inf.0
   <|------------------------|-----------------------|>
   <--------- -nan.0 -------> <-------- +nan.0 ------->
   <---------------------- ~nan.0 -------------------->

(/ -0.0)    => -inf.0

(/ 0)       => ~inf.0 (or basic ~nan.0)

(/ +0.0)    => +inf.0

(/ -inf.0 +0.0) => -nan.0 (or basic ~nan.0)

(/ ~inf.0 +0.0) => ~nan.0

(/ +inf.0 +0.0) => +nan.0 (or basic ~nan.0)

Enabling a basic implementation to simply map:

  ~inf.0 -nan.0 +nan.0 => ~nan.0