[sv-ec] semantics of wildcard bins

The last last paragraph of the section on wildcard bins (18.4.3) states:

"A wildcard bin definition only considers 2-state values; sampled values
containing X or Z are excluded. Thus, the range of values covered by a
wildcard bin is established by replacing every wildcard digit by 0 to
compute the low bound and 1 to compute the high bound."


1) The statement about the range of values is not right or is confusing.

   For example:
	wildcard bins bx = { 4'b?0?0 };
   This does not cover the values in the range 0000 to 1010. It doesn't
cover 0001.

2) What does it mean that sampled values containing X or Z are excluded.

   For example:
	wildcard bins bx = { 4'b?0?0 };
   I would expect that if the sample value is:
        0000	- increment the bin count
        1000      - increment the bin count
        0001      - don't increment
        000X 	- don't increment
        0010      - increment
        00X0      - increment
        00Z0      - increment
    However, the text seems to indicate that the last two sample values
are excluded and
    so don't increment the bin count. 

3) How many bins are created for 
    	wildcard bins bx[] = { 4'b?0?0, 4'b?000, 4'b00?0 }
   I would expect that 3 bins are created.

4) How are wildcard ignore_bins handled?
    For example:
	bins BA[2] = { 2'b00, 2'b1x };
      bins BB[2] = { 2'b10, 2'b0x };
	wildcard bins BC = { 2'b0?, 2'b11 }
      wildcard ignore_bins ivals = { 2'b00, 2'b?0, 2'b0? };
      ignore_bins vals = { 2'b01, 2'b00, 2'b0x, 2'b0z };

    The ignore value 2'b00 will be removed from the first BA bin causing
the 
    bin to be ignored. 
    Will the ignore value 2'b?0 remove the 2'b10 value from BB ?
    Will the list of values in the last ignore_bins remove the wildcard 
    value 2'b0 from BC ?

Ray