On Tue, Sep 13, 2011 at 12:04 PM, Panicz Maciej Godek <godek.mac...@gmail.com> wrote: > 2011/9/13, Andrew Gwozdziewycz <apg...@gmail.com>: >> >> Seems likely that you could use `syntax-case' to create a `let` out of >> these: >> >> (define-syntax progv >> (lambda (stx) >> (define (create-bindings syms vals) >> (datum->syntax stx (zip (syntax->datum syms) (syntax->datum vals)))) >> (syntax-case stx () >> ((_ symbols values body ...) >> (with-syntax ((bindings (create-bindings #'symbols #'values))) >> #'(let bindings >> (begin body ...))))))) >> >> >> >> ;; usage >> (progv (foo bar baz) (1 2 3) >> (format (current-output-port) "Values: ~a ~a ~a\n" foo bar baz)) >> ;; output: "Values: 1 2 3" > > Hey, > thanks for this code, maybe one day I will be able to comprehend it :) > for now, the problem is that I want to bind the variables that are > contained within a list, and that I don't know what's in that list. > > So, the following code should work as well: > (let ((s '(foo bar baz)) > (v '(1 2 3))) > (progv s v > (+ foo bar baz))) > ===> 6
Ah, yes. I believe there's no way around using eval here. The difficulty of course is compile time vs. runtime. -- http://www.apgwoz.com
