[J3] Thoughts on the semantics of generics

[Van Snyder]

On Wed, 2018-08-08 at 20:43 -0600, William Clodius via J3 wrote:
> Iterators and maps would often be simplified if Fortran
> included co-routines. 

If we had done coroutines early on, and allowed to specify a coroutine
with a particular interface, that included an unlimited polymorphic
argument, in the control information list of a data transfer statement,
to process each list item, we wouldn't have needed defined I/O.

I suggested a procedure for this purpose in conversation in February
1997, and one of the developers (IIRC, Keith) gave me the "sign of the
cross warding off a vampire," saying processors had gone to great
lengths to make that especially difficult for users.  This was before we
invented unlimited polymorphic.