Omission in the Ada Standard

[rleif@rleif.com (Robert C. Leif)]

While I was working on my latest project, the CellFuge, I was shocked
to learn that Jerry van Dijk's Io_Ports package that I have did not
compile with GNAT. I do need an up to date version. Since the Intel
Pentium class of processors and their clones are a very large part of
the software market, the possibility of port based IO should be
included in Ada.  I would suggest a child library of Package System.
Something like the source text below. The with System and use System
were included to permit compilation.
with System;
use System;
package System.Ports is
   type Port is new Address; 
   Null_Port : constant Port := Port (Null_Address);  
   Port_Unit : constant      := Storage_Unit;  

   -- Address Comparison: 
   function "<" (
         Left,        
         Right : Port ) 
     return Boolean; 
   function "<=" (
         Left,        
         Right : Port ) 
     return Boolean; 
   function ">" (
         Left,        
         Right : Port ) 
     return Boolean; 
   function ">=" (
         Left,        
         Right : Port ) 
     return Boolean; 
   function "=" (
         Left,        
         Right : Port ) 
     return Boolean; 
   -- function "/=" (Left, Right : Port) return Boolean; 
   -- "/=" is implicitly defined 
end System.Ports;
This would be followed by variants of the other System child
libraries. One way to do this is to create a generic package that
could be instantiated into both System and Ports.
Bob
Robert C. Leif, Ph.D.
Email rleif@rleif.com