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- To: CL-Cleanup@SAIL.Stanford.EDU
- Subject: Issue: IN-SYNTAX?
- From: Jon L White <firstname.lastname@example.org>
- Date: Thu, 27 Oct 88 22:45:18 PDT
I'm still very serious about the question of the default
package/readtable/read-base to be in effect when LOAD and
COMPILE-FILE start to work. I think the choice made way back
when, to let all of these assume their dynamic value current at
the time of the call to LOAD etc, has been counter-productive.
It means that normal files *cannot* be guaranteed to be loadable;
the caller of LOAD must at least guarantee that (1) some reasonable
readtable is in effect, (2) that either read-base is 10 or the file has
isolated itself against integer bases, and (3) that the current package
is "reasonable enough" to get something correctly read-in for the initial
IN-PACKAGE or the file has no unqualified symbols. [Note that very few
users write LISP:IN-PACKAGE -- not even those actually involved in
writing portable code!]. While it is reasonable for a file to have
something in it like:
(in-syntax :package sys:big-loser :read-base 16)
and thus be parsed in a truly non-standard way, I can think of no
other standardized computer language that leaves so much of its
syntax to environmental accidents rather than to clear specification.
I've "looked ahead" [actually "jumped around"] in my mail file to see
Kent's proposal for STANDARD-VALUE; while quite interesting in its own
right, it is more focused at shielding the debugger. Furthermore,
only 3 of the proposed 14 "standard values" would be involved in simple
Is there anyone else in this community simiarly concerned about specifying
a standard "foot to stand on", for the syntax of LOADing files? It may
be too late to bring up such an incompatible change now, but I still
think it is a serious problem.
-- JonL --