set! weirdness

From: Matthew Liggett <mliggett_at_onyx.chem.indiana.edu>
Date: Mon, 26 Sep 94 16:22:15 EST

I have an alist which is built like so:

(define al '((varname . value) (varname . value)))

However if I try to do this:

(let ([head (car al)]
      [tail (cdr al)])
   (set! (car head) (cdr head)))

...then STk complains that the 1st argument to set! "(car head)" is not
a symbol.

Of course (symbol? (car head)) returns #t

Any ideas? Is there an easier way to do this?

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Received on Mon Sep 26 1994 - 22:15:53 CET