> Actually, the datatypes were made first class to make I/O layerable in
> a first class way. If the datatype constructors were done in I/O then
> the decoding functions that are part of MPI-2 but not in I/O would not
> be able to return the calling sequence used - just an equivalent one.
> Moving them out of I/O means that they are no different - which they
> would be if layered.
So this means that there are other things in MPI IO that are
non-layerable. That is, just like one cannot add a function to
MPI::Comm, one cannot add two more functions to MPI::Datatype.
{+} Jeff Squyres
{+} squyres@cse.nd.edu
{+} Perpetual Obsessive Notre Dame Student Craving Utter Madness
{+} "I came to Notre Dame for 4 years and ended up staying for a
decade."