Joel Ray Holveck wrote:

> As a concrete example, suppose (as I did in a program I recently
> wrote) that you have a string with several arbitrary variable names
> you need to substitute in, and a hash with their values. This can be
> done in one line in Perl:
> # $string holds something like:
> # 'The $dimension of the $obj is $length cm.'
> # %vars holds something like:
> # { $dimension => length, $obj => plank, $length => 105 }
> $string =~ s/\$(\S+)/$vars->{$1}/g;
>
> Now, look at a Lisp parallel. You have a list, and you want to
> substitute keywords with their values from an alist:
> ;; LIST holds something like:
> ;; (the :dimension of the :object is :value cm)
> ;; VARS holds something like:
> ;; ((:dimension . length) (:object . plank) (:value . 105))
> (mapcar #'(lambda (elt)
> (if (keywordp elt)
> (cdr (assoc elt vars))
> elt))
> list)

newLISP

(define str "The $dimension of the $obj is $length cm.")
(define table '((dimension "length") (obj "plank") (length "105")))

(replace "\\$(\\w+)" str (lookup (sym $1) table) 0)

"The length of the plank is 105 cm."