r4666: *** empty log message ***

[kmrcl.git] / strings.lisp

diff --git a/strings.lisp b/strings.lisp
index d8c0e439a1383bf383ea96c20c44374608a81c75..45c2d7a54ba27e5414a4b458de3990f4d6863a4e 100644 (file)
--- a/strings.lisp
+++ b/strings.lisp
@@ -7,7 +7,7 @@
 ;;;; Programmer:    Kevin M. Rosenberg
 ;;;; Date Started:  Apr 2000
 ;;;;
-;;;; $Id: strings.lisp,v 1.9 2003/04/28 21:12:27 kevin Exp $
+;;;; $Id: strings.lisp,v 1.10 2003/04/28 23:51:59 kevin Exp $
 ;;;;
 ;;;; This file, part of KMRCL, is Copyright (c) 2002 by Kevin M. Rosenberg
 ;;;;
@@ -90,12 +90,7 @@
 
 (defun substitute-string-for-char (procstr match-char subst-str) 
   "Substitutes a string for a single matching character of a string"
-  (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)))
+  (replace-chars-strings procstr (list (cons match-char subst-str))))
 
 (defun string-substitute (string substring replacement-string)
   "String substitute by Larry Hunter. Obtained from Google"
@@ -114,10 +109,11 @@
          replacement-string))
       (setq last-end (+ next-start substring-length)))))
 
-
 (defun string-trim-last-character (s)
-"Return the string less the last character"
-  (subseq s 0 (1- (length s))))
+  "Return the string less the last character"
+  (aif (plusp (length s))
+       (subseq s 0 (1- it))
+       s))
 
 (defun string-hash (str &optional (bitmask 65535))
   (let ((hash 0))
@@ -144,9 +140,7 @@
   (when (stringp str)
     (null (find-if #'not-whitespace? str))))
 
-(defun string-replace-chars-strings (str repl-alist)
-  "Replace all instances of a chars with a string. repl-alist is an assoc
-list of characters and replacement strings."
+(defun replaced-string-length (str repl-alist)
   (declare (string str))
   (let* ((orig-len (length str))
         (new-len orig-len))
@@ -157,32 +151,39 @@ list of characters and replacement strings."
             (match (assoc c repl-alist :test #'char=)))
        (declare (character c))
        (when match
-         (incf new-len (length (cdr match))))))
-    (let ((new-string (make-string new-len))
-         (i 0))
-      (declare (string new-string)
-              (fixnum i))
-      (dotimes (i orig-len)
-       (declare (fixnum i))
-       (let* ((c (char str i))
-              (match (assoc c repl-alist :test #'char=)))
-         (declare (character c))
-         (if match
-             (let* ((subst (cdr match))
-                    (len (length match)))
-               (dotimes (j len)
-                 (setf (char new-string i) (char subst j))
-                 (incf i))
-               (decf i))
-           (progn
-             (setf (char new-string i) c)))))
-      new-string)))
+         (incf new-len (1- (length (cdr match)))))))
+    new-len))
+
+(defun string-replace-chars-strings (str repl-alist)
+  "Replace all instances of a chars with a string. repl-alist is an assoc
+list of characters and replacement strings."
+  (declare (simple-string str))
+  (do* ((orig-len (length str))
+       (new-string (make-string (replaced-string-length str repl-alist)))
+       (spos 0 (1+ spos))
+       (dpos 0))
+      ((>= spos orig-len)
+       new-string)
+    (declare (fixnum spos dpos) (simple-string new-string))
+    (let* ((c (char str spos))
+          (match (assoc c repl-alist :test #'char=)))
+      (declare (character c))
+      (if match
+         (let* ((subst (cdr match))
+                (len (length subst)))
+           (declare (fixnum len))
+           (dotimes (j len)
+             (declare (fixnum j))
+             (setf (char new-string dpos) (char subst j))
+             (incf dpos)))
+       (progn
+         (setf (char new-string dpos) c)
+         (incf dpos))))))
 
 (defun escape-xml-string (string)
   "Escape invalid XML characters"
-  (string-replace-char-string
-   (string-replace-char-string string #\& "&")
-   #\< "&lt;"))
+  (string-replace-chars-strings 
+   string '((#\& . "&amp;") (#\> . "&gt;") (#\< . "&lt;"))))
 
 (defun string-replace-char-string (string repl-char repl-str)
   "Replace all occurances of repl-char with repl-str"