Re: Derived types and allocatable

James Van Buskirk wrote:
> "James Giles" <jamesgiles@[EMAIL PROTECTED]
> wrote in message
> news:_2rVj.186212$D_3.46099@[EMAIL PROTECTED]
>
>> Some people might read the above as implying that there's an
>> incompatibility between F95 and F2003.  That's not quite right.  The
>> syntax and semantics of those cases allowed by the old standard
>> are identical in the new standard.  However, the new standard
>> provides a meaning for cases the older standard explicitly
>> prohibited. No standard conforming F95 program should behave any
>> differently under F2003.
>
> Yes, but a standard conforming f03 program may be interpreted as
> an f95 program with extensions.

That's the price any implementor pays for allowing extensions:
future standards may use the same syntax for some different
meaning.  It's also the price any user pays for using extensions:
future standards may require the code to be changed.  All
the standard can guarantee when they maintain backward
compatibility is the above: no previously conforming program
should behave differently under the new standard.  Previously
non-conforming programs have no guarantees at all.

-- 
J. Giles

"I conclude that there are two ways of constructing a software
design: One way is to make it so simple that there are obviously
no deficiencies and the other way is to make it so complicated
that there are no obvious deficiencies."   --  C. A. R. Hoare