Re: Is strong typing worth the cost?

[Gary Scott <Gary.L.Scott@lmtas.lmco.com>]

Preben Randhol wrote:
> 
> On Fri, 03 May 2002 10:17:45 GMT, Gary Scott wrote:
> > It (IMPLICIT NONE) is standard in F90 (including NAG F90).  It was an
> > extension only in FORTRAN 77.
> 
> Yes, but all the old code is F77 and we want to be able to compile it on
> other platforms as F77 too :-)

But that was the point of Dan Nagle.  There are almost certainly NO
FORTRAN 77 compilers that do not support IMPLICIT NONE, since it was
required by MIL-STD-1753 (or whatever it was).  True, it isn't 100%
standard, but unless the code is purely numerical (and maybe even then),
I'd almost bet, having never seen it, that it isn't 100% standard
already.  And while IMPLICIT NONE SHOULD have been made the default at
Fortran 90 but wasn't, it is an improvement over the use of logical for
implicit declarations (i.e. completely eliminates implicit typing).  It
does nothing with regard to mixed mode conversions, but I find the
Fortran rules quite straightforward there.