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Re: user survey
1. Single quote read syntax:
Oy vay. I don't THINK I have any code that will break, but unless
there's some really compelling need to fiddle with it (I'm not impressed
by the ability to redefine QUOTE), I'd leave it alone.
2. The value of T.
(At first I thought you were asking about the value of the T LANGUAGE!)
I have some code that depends on the fact that T evaluates to T (or
more accurately, is GOING to evaluate to true), which is wrong, since
you can bind T to NIL or 3 or anything you like. I could probably
change the code, but I think it's important that the logical contants
have a read-syntax, like numbers and strings. Yes, we could use .TRUE.
and .FALSE. but why bother? I think it's a good idea to leave T and
3. Semantics of LET.
(DESTRUCTURE (((A (B C)) FOO)) . body) is really peculiar notation.
It's not A, B, and C that are stored in a list structure, it's FOO.
But if we keep that idea, then I'd do away with DESTRUCTURE and notate
multiple-value bindings thus:
(LET ( (P aaa)
((A B C) bbb)
('(X (Y Z)) ccc)
('#(I J K) ddd) ) . body)
The first case is the standard one.
The second case is a generic multiple-value assignment; bbb could be
any sort of thing that "returned" three values. We simply guarantee
that they'd be bound to A, B, and C, in that order. The compiler might
be able to do great things with this if it knew something about bbb.
The other two cases are multiple-value bindings that are
datatype-specific: ccc must be a list structure (this is how you could
notate DESTRUCTURE), and ddd must be a vector.
Except in case 1, you probably want to allow the value to be "longer"
than the variable-structure; e.g., we won't insist that (VECTOR-LENGTH
ddd) be 3, although it shouldn't be less than 3. Note that
(LET (( P aaa)) ...) would not be equivalent to
(LET (((P) aaa)) ...).
Note also that only in case 2 can we use anything other than a simple,
linear sequence of variables.
Unfortunately, the generic case (2) doesn't square with SET. While
(SET P aaa) is OK now, and we could implement (SET '(X (Y Z)) ccc)
and (SET '#(I J K) ddd) to do what we want, (SET (A B C) bb) already
means something. *sigh*
Finally, I'm not in favor of the DEFINE/LABELS interpretation at all.
I don't even like the triple-parenthesis notation in LABELS, but then
my Apollo prints ^ as the Greek letter lambda, so I tend to use the