Section 8.19
inside operator

 

In 8.19, REPLACE

 

                Integral expressions also use the equality operator, except that a z inside a value in the set is treated as a don’t care and that bit position shall not be considered. Note that unlike comparisons performed by the casez statement, z values in the expression on the left-hand side are not treated as a don’t-care; the don’t-care is unidirectional.

 

 

WITH

 

            Integral expressions also use the equality operator, except that a z inside a value in the set is treated as a don’t care and that bit position shall not be considered. Note that unlike comparisons performed by the casez statement, z values in the expression on the left-hand side are not treated as a don’t-care; the don’t-care is unidirectional.    Integral expressions use the wildcard equality (==?) operator, so that an x or z bit in a value in the set is treated as a don't-care  in that bit position (see 8.5). As with wildcard equality, an x or z in the expression on the left-hand side of the inside operator is not treated as a don't-care.