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Subject: Re: (j3.2006) (SC22WG5.3623) [ukfortran] A comment on John
	Wallin's comments	on	Nick MacLaren's comments
From: Van Snyder <Van.Snyder@jpl.nasa.gov>
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On Wed, 2008-11-05 at 15:28 -0800, N.M. Maclaren wrote:
> Anyway, I regard the right solution to this is that every derived type
> should have code and decode primitives, and that you should transfer
> the encoded form.  You need them for a great many purposes, including
> unformatted I/O, not just MPI.
> 
> > The important thing to note is that every time a grad student adds a
> > single element to the data structure, you have to alter the block
> > counts and sizes by hand.
> 
> Sorry, but no.  There are better solutions.  I agree that none are
> pretty, and all involve enforcing strict discipline on the
> programmers, but they have been known since time immemorial.
> Parameterisation is the key.

Clause 9 of the Fortran standard already does this.  It makes my head
hurt to write the encode and decode primitives for every derived type,
and then rewrite them whenever a tiny detail changes.  I suppose I could
use internal I/O, which on some systems many years ago was provided by
ENCODE and DECODE statements.  I'd rather use coarrays, and if they're
not available I'd rather use unformatted I/O.

-- 
Van Snyder                    |  What fraction of Americans believe 
Van.Snyder@jpl.nasa.gov       |  Wrestling is real and NASA is fake?
Any alleged opinions are my own and have not been approved or
disapproved by JPL, CalTech, NASA, the President, or anybody else.