(substitute-string-for-char s #\' "''"))
(defun substitute-string-for-char (procstr match-char subst-str)
-"Substitutes a string for a single matching character of a string"
- (declare (type string procstr))
- (let ((pos (position match-char procstr)))
- (if pos
- (concatenate 'string
- (subseq procstr 0 pos) subst-str
- (substitute-string-for-char
- (subseq procstr (1+ pos)) match-char subst-str))
- procstr)))
+ "Substitutes a string for a single matching character of a string"
+ (when procstr
+ (locally
+ (declare (type string procstr))
+ (let ((pos (position match-char procstr)))
+ (if pos
+ (concatenate 'string
+ (subseq procstr 0 pos) subst-str
+ (substitute-string-for-char
+ (subseq procstr (1+ pos)) match-char subst-str))
+ procstr)))))
(defun position-char (char string start max)