+
+(macrolet ((define-trimmer-transform (fun-name leftp rightp)
+ `(deftransform ,fun-name ((char-bag string)
+ (t simple-string))
+ (let ((find-expr
+ (if (constant-lvar-p char-bag)
+ ;; If the bag is constant, use MEMBER
+ ;; instead of FIND, since we have a
+ ;; deftransform for MEMBER that can
+ ;; open-code all of the comparisons when
+ ;; the list is constant. -- JES, 2007-12-10
+ `(not (member (schar string index)
+ ',(coerce (lvar-value char-bag) 'list)
+ :test #'char=))
+ '(not (find (schar string index) char-bag :test #'char=)))))
+ `(flet ((char-not-in-bag (index)
+ ,find-expr))
+ (let* ((end (length string))
+ (left-end (if ,',leftp
+ (do ((index 0 (1+ index)))
+ ((or (= index (the fixnum end))
+ (char-not-in-bag index))
+ index)
+ (declare (fixnum index)))
+ 0))
+ (right-end (if ,',rightp
+ (do ((index (1- end) (1- index)))
+ ((or (< index left-end)
+ (char-not-in-bag index))
+ (1+ index))
+ (declare (fixnum index)))
+ end)))
+ (if (and (eql left-end 0)
+ (eql right-end (length string)))
+ string
+ (subseq string left-end right-end))))))))
+ (define-trimmer-transform string-left-trim t nil)
+ (define-trimmer-transform string-right-trim nil t)
+ (define-trimmer-transform string-trim t t))
+