+;;; string.lisp
+
+;; JSCL is free software: you can redistribute it and/or
+;; modify it under the terms of the GNU General Public License as
+;; published by the Free Software Foundation, either version 3 of the
+;; License, or (at your option) any later version.
+;;
+;; JSCL is distributed in the hope that it will be useful, but
+;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+;; General Public License for more details.
+;;
+;; You should have received a copy of the GNU General Public License
+;; along with JSCL. If not, see <http://www.gnu.org/licenses/>.
+
+(defun string (x)
+ (cond ((stringp x) x)
+ ((symbolp x) (symbol-name x))
+ (t (char-to-string x))))
+
+(defun string= (s1 s2)
+ (let ((n (length s1)))
+ (when (= (length s2) n)
+ (dotimes (i n t)
+ (unless (char= (char s1 i) (char s2 i))
+ (return-from string= nil))))))
+
+(define-setf-expander char (string index)
+ (let ((g!string (gensym))
+ (g!index (gensym))
+ (g!value (gensym)))
+ (list (list g!string g!index)
+ (list string index)
+ (list g!value)
+ `(aset ,g!string ,g!index ,g!value)
+ `(char ,g!string ,g!index))))