On Mon, 2017-04-03 at 20:24 +0000, Bill Long wrote:
> The REAL32, REAL64, and REAL128 constants, as we as INT8, INT16,
> INT32, and INT64 constants for integers, were added as a convenience
> for users. "The requirement is to provide a simplified means to select
> the most commonly desired real and integer kinds.” It is far better
> than the old *n form because these constants can be used in
> standard-conforming statements. The constants also provide useful
> information in that negative values indicate that the particular KIND
> is not supported.
Since Fortran 90, at least some users asked for a way to specify both
the number of digits and the radix for integers and floating point
fractions. That request has been repeatedly rebuffed.
> I would hope that REAL*n is no longer in “widespread usage”.
> Although I do still see the archaic CHARACTER*n being used, instead of
> the more modern CHARACTER(n).
>
> Cheers,
> Bill
>
>
> On Apr 3, 2017, at 11:00 AM, Vipul Parekh <[log in to unmask]> wrote:
>
> > Steve Lionel, previously at Intel, pointed out in a recent blogpost
> at http://intel.ly/2nZSxoE) that "Fortran 2008 extended intrinsic
> module ISO_FORTRAN_ENV to include named constants .. REAL32, REAL64
> and REAL128 whose values correspond to the kinds of real .. that
> occupy the stated number of bits. .. In my view, this is little better
> than the old *n extension in that it tells you that a type fits in
> that many bits, but nothing else about it."
> >
> > So I'm just curious as to why as recently as Fortran 2008, something
> gets introduced into the standard whose value or use case seems
> unclear. Would anybody on this mailing list know that the standards
> committee had in mind i.e., what were the use case(s), say, for REAL64
> and REAL128 when they introduced to the ISO_FORTRAN_ENV intrinsic
> module? Were they added to address somehow the widespread usage of
> REAL*n constructs and if so, how did the committee hope that would
> materialize?
> >
> > Any feedback is appreciated.
> >
> > Best Regards,
> > Vipul Parekh
> >
> >
>
> Bill Long [log in to unmask]
> Principal Engineer, Fortran Technical Support & voice: 651-605-9024
> Bioinformatics Software Development fax: 651-605-9143
> Cray Inc./ 2131 Lindau Lane/ Suite 1000/ Bloomington, MN 55425
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