New hook filter-buffer-substring-functions.

* simple.el (with-wrapper-hook): Move.
(buffer-substring-filters): Mark obsolete.
(filter-buffer-substring-functions): New variable.
(buffer-substring-filters): Use it.  Remove unused arg `noprops'.

3 files changed, 78 insertions, 75 deletions

diff --git a/etc/NEWS b/etc/NEWS
index e4288684818..6fa940143bb 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -181,6 +181,8 @@ Secret Service API requires D-Bus for communication.
 
 * Lisp changes in Emacs 24.1
 
+** buffer-substring-filters is obsoleted by filter-buffer-substring-functions.
+
 ** New completion style `substring'.
 
 ** Image API
diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 86b73ddd292..a7414aa2586 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,5 +1,10 @@
 2010-05-02  Stefan Monnier  <monnier@iro.umontreal.ca>
 
+        * simple.el (with-wrapper-hook): Move.
+        (buffer-substring-filters): Mark obsolete.
+        (filter-buffer-substring-functions): New variable.
+        (buffer-substring-filters): Use it.  Remove unused arg `noprops'.
+
         Use a mode-line spec rather than a static string in Semantic.
         * cedet/semantic/util-modes.el:
         (semantic-minor-modes-format): New var to replace...
diff --git a/lisp/simple.el b/lisp/simple.el
index cc70409ccd4..37ad0d81ca0 100644
--- a/lisp/simple.el
+++ b/lisp/simple.el
@@ -2688,6 +2688,60 @@ These commands include \\[set-mark-command] and \\[start-kbd-macro]."
   (reset-this-command-lengths)
   (restore-overriding-map))
 
+;; This function is here rather than in subr.el because it uses CL.
+(defmacro with-wrapper-hook (var args &rest body)
+  "Run BODY wrapped with the VAR hook.
+VAR is a special hook: its functions are called with a first argument
+which is the \"original\" code (the BODY), so the hook function can wrap
+the original function, or call it any number of times (including not calling
+it at all).  This is similar to an `around' advice.
+VAR is normally a symbol (a variable) in which case it is treated like
+a hook, with a buffer-local and a global part.  But it can also be an
+arbitrary expression.
+ARGS is a list of variables which will be passed as additional arguments
+to each function, after the initial argument, and which the first argument
+expects to receive when called."
+  (declare (indent 2) (debug t))
+  ;; We need those two gensyms because CL's lexical scoping is not available
+  ;; for function arguments :-(
+  (let ((funs (make-symbol "funs"))
+        (global (make-symbol "global"))
+        (argssym (make-symbol "args")))
+    ;; Since the hook is a wrapper, the loop has to be done via
+    ;; recursion: a given hook function will call its parameter in order to
+    ;; continue looping.
+    `(labels ((runrestofhook (,funs ,global ,argssym)
+                 ;; `funs' holds the functions left on the hook and `global'
+                 ;; holds the functions left on the global part of the hook
+                 ;; (in case the hook is local).
+                 (lexical-let ((funs ,funs)
+                               (global ,global))
+                   (if (consp funs)
+                       (if (eq t (car funs))
+                           (runrestofhook
+                            (append global (cdr funs)) nil ,argssym)
+                         (apply (car funs)
+                                (lambda (&rest ,argssym)
+                                  (runrestofhook (cdr funs) global ,argssym))
+                                ,argssym))
+                     ;; Once there are no more functions on the hook, run
+                     ;; the original body.
+                     (apply (lambda ,args ,@body) ,argssym)))))
+       (runrestofhook ,var
+                      ;; The global part of the hook, if any.
+                      ,(if (symbolp var)
+                           `(if (local-variable-p ',var)
+                                (default-value ',var)))
+                      (list ,@args)))))
+
+(defvar filter-buffer-substring-functions nil
+  "Wrapper hook around `filter-buffer-substring'.
+The functions on this special hook are called with 4 arguments:
+  NEXT-FUN BEG END DELETE
+NEXT-FUN is a function of 3 arguments (BEG END DELETE)
+that performs the default operation.  The other 3 arguments are like
+the ones passed to `filter-buffer-substring'.")
+
 (defvar buffer-substring-filters nil
   "List of filter functions for `filter-buffer-substring'.
 Each function must accept a single argument, a string, and return
@@ -2697,46 +2751,34 @@ the next.  The return value of the last function is used as the
 return value of `filter-buffer-substring'.
 
 If this variable is nil, no filtering is performed.")
+(make-obsolete-variable 'buffer-substring-filters
+                        'filter-buffer-substring-functions "24.1")
 
-(defun filter-buffer-substring (beg end &optional delete noprops)
+(defun filter-buffer-substring (beg end &optional delete)
   "Return the buffer substring between BEG and END, after filtering.
-The buffer substring is passed through each of the filter
-functions in `buffer-substring-filters', and the value from the
-last filter function is returned.  If `buffer-substring-filters'
-is nil, the buffer substring is returned unaltered.
+The filtering is performed by `filter-buffer-substring-functions'.
 
 If DELETE is non-nil, the text between BEG and END is deleted
 from the buffer.
 
-If NOPROPS is non-nil, final string returned does not include
-text properties, while the string passed to the filters still
-includes text properties from the buffer text.
-
-Point is temporarily set to BEG before calling
-`buffer-substring-filters', in case the functions need to know
-where the text came from.
-
 This function should be used instead of `buffer-substring',
 `buffer-substring-no-properties', or `delete-and-extract-region'
 when you want to allow filtering to take place.  For example,
-major or minor modes can use `buffer-substring-filters' to
+major or minor modes can use `filter-buffer-substring-functions' to
 extract characters that are special to a buffer, and should not
 be copied into other buffers."
-  (cond
-   ((or delete buffer-substring-filters)
-    (save-excursion
-      (goto-char beg)
-      (let ((string (if delete (delete-and-extract-region beg end)
-                      (buffer-substring beg end))))
-        (dolist (filter buffer-substring-filters)
-          (setq string (funcall filter string)))
-        (if noprops
-            (set-text-properties 0 (length string) nil string))
-        string)))
-   (noprops
-    (buffer-substring-no-properties beg end))
-   (t
-    (buffer-substring beg end))))
+  (with-wrapper-hook filter-buffer-substring-functions (beg end delete)
+    (cond
+     ((or delete buffer-substring-filters)
+      (save-excursion
+        (goto-char beg)
+        (let ((string (if delete (delete-and-extract-region beg end)
+                        (buffer-substring beg end))))
+          (dolist (filter buffer-substring-filters)
+            (setq string (funcall filter string)))
+          string)))
+     (t
+      (buffer-substring beg end)))))
 
 
 ;;;; Window system cut and paste hooks.
@@ -6505,52 +6547,6 @@ the first N arguments are fixed at the values with which this function
 was called."
   (lexical-let ((fun fun) (args1 args))
     (lambda (&rest args2) (apply fun (append args1 args2)))))
-
-;; This function is here rather than in subr.el because it uses CL.
-(defmacro with-wrapper-hook (var args &rest body)
-  "Run BODY wrapped with the VAR hook.
-VAR is a special hook: its functions are called with a first argument
-which is the \"original\" code (the BODY), so the hook function can wrap
-the original function, or call it any number of times (including not calling
-it at all).  This is similar to an `around' advice.
-VAR is normally a symbol (a variable) in which case it is treated like
-a hook, with a buffer-local and a global part.  But it can also be an
-arbitrary expression.
-ARGS is a list of variables which will be passed as additional arguments
-to each function, after the initial argument, and which the first argument
-expects to receive when called."
-  (declare (indent 2) (debug t))
-  ;; We need those two gensyms because CL's lexical scoping is not available
-  ;; for function arguments :-(
-  (let ((funs (make-symbol "funs"))
-        (global (make-symbol "global"))
-        (argssym (make-symbol "args")))
-    ;; Since the hook is a wrapper, the loop has to be done via
-    ;; recursion: a given hook function will call its parameter in order to
-    ;; continue looping.
-    `(labels ((runrestofhook (,funs ,global ,argssym)
-                 ;; `funs' holds the functions left on the hook and `global'
-                 ;; holds the functions left on the global part of the hook
-                 ;; (in case the hook is local).
-                 (lexical-let ((funs ,funs)
-                               (global ,global))
-                   (if (consp funs)
-                       (if (eq t (car funs))
-                           (runrestofhook
-                            (append global (cdr funs)) nil ,argssym)
-                         (apply (car funs)
-                                (lambda (&rest ,argssym)
-                                  (runrestofhook (cdr funs) global ,argssym))
-                                ,argssym))
-                     ;; Once there are no more functions on the hook, run
-                     ;; the original body.
-                     (apply (lambda ,args ,@body) ,argssym)))))
-       (runrestofhook ,var
-                      ;; The global part of the hook, if any.
-                      ,(if (symbolp var)
-                           `(if (local-variable-p ',var)
-                                (default-value ',var)))
-                      (list ,@args)))))
 
 ;; Minibuffer prompt stuff.