Replace LETREC with "relaxed" internal DEFINES.

[ramsdell%linus@mitre-bedford.ARPA]

>From the agenda:
>RELAX THE LETREC RESTRICTION.  Require implementations to find
>an order that works, if any does.  Issue:  not computable?

I think the whole point of relaxing the LETREC restrictions was to
allow the replacement of LETREC's and many LET's with local DEFINE's.
If the strong components of some local DEFINE's dependency graph is
topologically sorted, an interpreter or compiler can generate the best
combination of LETREC's and LET's.  Programmers would then be freed of
having to think about current large distinction between local
definitions and top level definitions.  The issue is:

RELAX LOCAL DEFINES RESTRICTIONS AND FLUSH LETREC.  Require
implementations to treat local DEFINE's as the best combination of
LET's and LETREC's.

John

PS. I would like to see file compilers treat top level defines just as
I suggest local defines be treated.  Why should the order be so
important within files?