"Maciek Godek" <[EMAIL PROTECTED]> writes:
> I've tried to do it using a "procedure with
> setter", but the problem is that set! doesn't
> evaluate its first argument (as long as it's a
> symbol), so I'd have to wrap everything
> up in macros to obtain:
> (set! (vector-location v 1) 10)
Actually, if you (use-syntax (ice-9 syncase)), you should be able to
define lexical symbol-macros that expand a single symbol, even in a
set! place, something like:
(define v #(1 2 3))
(define-syntax v1
(lambda (stx)
(syntax-case stx ()
(_ v))))
Obviously aliasing will serve:
(define-syntax alias-syntax
(syntax-rules ()
((_ form)
(lambda (stx)
(syntax-case stx ()
(_ (syntax form)))))))
(define-syntax defalias
(syntax-rules stx ()
((_ new form)
(define-syntax new (alias-syntax form)))))
(define-syntax let-alias
(syntax-rules ()
((_ ((new form) ...) body ...)
(let-syntax ((new (alias-syntax form)) ...) body ...))))
(defalias v1 (vector-ref v 1))
(set! v1 42)
(vector-ref v 1) ; => 42
--
a Mr. Fleming wishes to study bugs in smelly cheese; a Polish woman
wishes to sift through tons of Central African ore to find minute
quantities of a substance she says will glow in the dark; a Mr. Kepler
wants to hear the songs the planets sing.
--Carl Sagan, "The Demon-Haunted World"
