12:44 a.m.
APPROVE COMMIT
NOTE: This patch has been committed
# HG changeset patch
# User Aidan Kehoe <kehoea(a)parhasard.net>
# Date 1538350975 -3600
# Mon Oct 01 00:42:55 2018 +0100
# Node ID 9a9e9993b4125f9223cf1189c5cd4791075ea1e3
# Parent 45b565af61281f58888966bc576f3d0f5c0a50b0
Advise against #'marker-position in its docstring; follow this advice, lisp/
src/ChangeLog addition:
2018-10-01 Aidan Kehoe <kehoea(a)parhasard.net>
* marker.c (Fmarker_position):
Advise not to use this function in its docstring; give an example
of a restricted use case where it is reasonable.
lisp/ChangeLog addition:
2018-10-01 Aidan Kehoe <kehoea(a)parhasard.net>
* code-files.el (insert-file-contents):
* cus-edit.el (custom-redraw):
* font-lock.el (font-lock-fontify-syntactically-region):
* help.el (Help-princ-face):
* help.el (Help-prin1-face):
* help.el (help-symbol-regexp):
* indent.el (increase-left-margin):
* indent.el (decrease-left-margin):
* info.el (Info-find-file-node):
* info.el (Info-cease-edit):
* mouse.el (default-mouse-track-deal-with-down-event):
* select.el (select-convert-to-lineno):
* select.el (select-convert-to-sourceloc):
* simple.el (kill-region):
* simple.el (pop-global-mark):
* simple.el (signal-error-on-buffer-boundary):
* wid-edit.el (widget-setup):
* window-xemacs.el (restore-saved-window-parameters):
Don't call #'marker-position in the core Lisp code, as we have
just advised in its docstring.
man/ChangeLog addition:
2018-10-01 Aidan Kehoe <kehoea(a)parhasard.net>
* lispref/compile.texi (Different Behavior):
Mention the unfortunate algorithmic complexity of
#'marker-position when cautioning about the behaviour of (+ MARKER
0).
diff -r 45b565af6128 -r 9a9e9993b412 lisp/ChangeLog
--- a/lisp/ChangeLog Fri Sep 28 11:00:54 2018 +0100
+++ b/lisp/ChangeLog Mon Oct 01 00:42:55 2018 +0100
＠＠ -1,3 +1,26 ＠＠
+2018-10-01 Aidan Kehoe <kehoea(a)parhasard.net>
+
+ * code-files.el (insert-file-contents):
+ * cus-edit.el (custom-redraw):
+ * font-lock.el (font-lock-fontify-syntactically-region):
+ * help.el (Help-princ-face):
+ * help.el (Help-prin1-face):
+ * help.el (help-symbol-regexp):
+ * indent.el (increase-left-margin):
+ * indent.el (decrease-left-margin):
+ * info.el (Info-find-file-node):
+ * info.el (Info-cease-edit):
+ * mouse.el (default-mouse-track-deal-with-down-event):
+ * select.el (select-convert-to-lineno):
+ * select.el (select-convert-to-sourceloc):
+ * simple.el (kill-region):
+ * simple.el (pop-global-mark):
+ * simple.el (signal-error-on-buffer-boundary):
+ * wid-edit.el (widget-setup):
+ * window-xemacs.el (restore-saved-window-parameters):
+ Don't call #'marker-position in the core Lisp code, as we have
+ just advised in its docstring.
+
2018-09-28 Aidan Kehoe <kehoea(a)parhasard.net>
* byte-optimize.el (byte-optimize-car):
diff -r 45b565af6128 -r 9a9e9993b412 lisp/code-files.el
--- a/lisp/code-files.el Fri Sep 28 11:00:54 2018 +0100
+++ b/lisp/code-files.el Mon Oct 01 00:42:55 2018 +0100
＠＠ -536,12 +536,12 ＠＠
;; convention of post-read-conversion. We try to
;; support the old way. #### Should we kill this?
(funcall func (point) (marker-position endmark))
- (funcall func (- (marker-position endmark) (point))))))
+ (funcall func (- endmark (point))))))
(if visit
(progn
(set-buffer-auto-saved)
(set-buffer-modified-p nil)))))
- (setcar (cdr return-val) (- (marker-position endmark) (point))))
+ (setcar (cdr return-val) (- endmark (point))))
;; now finally set the buffer's `buffer-file-coding-system' ...
(if (run-hook-with-args-until-success 'insert-file-contents-post-hook
filename visit return-val)
diff -r 45b565af6128 -r 9a9e9993b412 lisp/cus-edit.el
--- a/lisp/cus-edit.el Fri Sep 28 11:00:54 2018 +0100
+++ b/lisp/cus-edit.el Mon Oct 01 00:42:55 2018 +0100
＠＠ -1646,8 +1646,10 ＠＠
(let ((line (count-lines (point-min) (point)))
(column (current-column))
(pos (point))
- (from (marker-position (widget-get widget :from)))
- (to (marker-position (widget-get widget :to))))
+ (from (widget-get widget :from))
+ (to (widget-get widget :to)))
+ (check-type from marker)
+ (check-type to marker)
(save-excursion
(widget-value-set widget (widget-value widget))
(custom-redraw-magic widget))
diff -r 45b565af6128 -r 9a9e9993b412 lisp/font-lock.el
--- a/lisp/font-lock.el Fri Sep 28 11:00:54 2018 +0100
+++ b/lisp/font-lock.el Mon Oct 01 00:42:55 2018 +0100
＠＠ -1640,18 +1640,18 ＠＠
(goto-char start)
(let ((lisp-like (font-lock-lisp-like major-mode))
- (cache (marker-position font-lock-cache-position))
+ (cache font-lock-cache-position)
state string beg depth)
;;
;; Find the state at the `beginning-of-line' before `start'.
- (if (eq start cache)
+ (if (= start cache)
;; Use the cache for the state of `start'.
(setq state font-lock-cache-state)
;; Find the state of `start'.
(if (null font-lock-beginning-of-syntax-function)
;; Use the state at the previous cache position, if any, or
;; otherwise calculate from `point-min'.
- (if (or (null cache) (< start cache))
+ (if (or (null (marker-buffer cache)) (< start cache))
(setq state (parse-partial-sexp (point-min) start))
(setq state (parse-partial-sexp cache start nil nil
font-lock-cache-state)))
diff -r 45b565af6128 -r 9a9e9993b412 lisp/help.el
--- a/lisp/help.el Fri Sep 28 11:00:54 2018 +0100
+++ b/lisp/help.el Mon Oct 01 00:42:55 2018 +0100
＠＠ -1314,11 +1314,10 ＠＠
(put-nonduplicable-text-property opoint (point standard-output)
'face face standard-output)))
((markerp standard-output)
- (let ((buf (marker-buffer standard-output))
- (pos (marker-position standard-output)))
+ (let ((pos (copy-marker standard-output)))
(princ object)
(put-nonduplicable-text-property
- pos (marker-position standard-output) 'face face buf)))
+ pos standard-output 'face face (marker-buffer standard-output))))
(t (princ object))))
;; replacement for `prin1' that puts the text in the specified face,
＠＠ -1330,11 +1329,10 ＠＠
(put-nonduplicable-text-property opoint (point standard-output)
'face face standard-output)))
((markerp standard-output)
- (let ((buf (marker-buffer standard-output))
- (pos (marker-position standard-output)))
+ (let ((pos (copy-marker standard-output)))
(prin1 object)
(put-nonduplicable-text-property
- pos (marker-position standard-output) 'face face buf)))
+ pos standard-output 'face face (marker-buffer standard-output))))
(t (prin1 object))))
(defvar help-symbol-regexp
diff -r 45b565af6128 -r 9a9e9993b412 lisp/indent.el
--- a/lisp/indent.el Fri Sep 28 11:00:54 2018 +0100
+++ b/lisp/indent.el Mon Oct 01 00:42:55 2018 +0100
＠＠ -213,12 +213,12 ＠＠
(if (bolp) (setq from (point)))
(goto-char to)
(setq to (point-marker)))
- (alter-text-property from (marker-position to) 'left-margin ; XEmacs
+ (alter-text-property from to 'left-margin ; XEmacs
(lambda (v) (max (- left-margin) (+ inc (or v 0)))))
- (indent-rigidly from (marker-position to) inc) ; XEmacs
+ (indent-rigidly from to inc) ; XEmacs
(if auto-fill-function
(save-excursion
- (fill-region from (marker-position to) nil t t))) ; XEmacs
+ (fill-region from to nil t t))) ; XEmacs
(move-marker to nil))
(defun decrease-left-margin (from to inc)
diff -r 45b565af6128 -r 9a9e9993b412 lisp/info.el
--- a/lisp/info.el Fri Sep 28 11:00:54 2018 +0100
+++ b/lisp/info.el Mon Oct 01 00:42:55 2018 +0100
＠＠ -781,7 +781,7 ＠＠
;; First get advice from tag table if file has one.
;; Also, if this is an indirect info file,
;; read the proper subfile into this buffer.
- (if (marker-position Info-tag-table-marker)
+ (if (marker-buffer Info-tag-table-marker)
(let (foun found-mode (m Info-tag-table-marker))
(save-excursion
(set-buffer (marker-buffer Info-tag-table-marker))
＠＠ -3119,7 +3119,7 ＠＠
(setq buffer-read-only t)
;; Make mode line update.
(set-buffer-modified-p (buffer-modified-p))
- (and (marker-position Info-tag-table-marker)
+ (and (marker-buffer Info-tag-table-marker)
(buffer-modified-p)
(message "Tags may have changed. Use Info-tagify if necessary")))
diff -r 45b565af6128 -r 9a9e9993b412 lisp/mouse.el
--- a/lisp/mouse.el Fri Sep 28 11:00:54 2018 +0100
+++ b/lisp/mouse.el Mon Oct 01 00:42:55 2018 +0100
＠＠ -1205,7 +1205,7 ＠＠
(markerp default-mouse-track-previous-point)
(eq (current-buffer)
(marker-buffer default-mouse-track-previous-point)))
- (marker-position default-mouse-track-previous-point)
+ (copy-marker default-mouse-track-previous-point)
(point)))
(default-mouse-track-set-point event default-mouse-track-window)
(if (not adjust)
diff -r 45b565af6128 -r 9a9e9993b412 lisp/select.el
--- a/lisp/select.el Fri Sep 28 11:00:54 2018 +0100
+++ b/lisp/select.el Mon Oct 01 00:42:55 2018 +0100
＠＠ -597,8 +597,8 ＠＠
((and (consp value)
(markerp (car value))
(markerp (cdr value)))
- (setq a (marker-position (car value))
- b (marker-position (cdr value))
+ (setq a (car value)
+ b (cdr value)
buf (marker-buffer (car value)))))
(save-excursion
(set-buffer buf)
＠＠ -649,8 +649,8 ＠＠
((and (consp value)
(markerp (car value))
(markerp (cdr value)))
- (setq a (marker-position (car value))
- b (marker-position (cdr value))
+ (setq a (car value)
+ b (cdr value)
buf (or (marker-buffer (car value))
(error "selection is in a killed buffer"))
file-name (buffer-file-name buf))))
diff -r 45b565af6128 -r 9a9e9993b412 lisp/simple.el
--- a/lisp/simple.el Fri Sep 28 11:00:54 2018 +0100
+++ b/lisp/simple.el Mon Oct 01 00:42:55 2018 +0100
＠＠ -1465,8 +1465,6 ＠＠
; (if region-hack (zmacs-deactivate-region)))))
;; start and end can be markers but the rest of this function is
;; written as if they are only integers
- (if (markerp start) (setq start (marker-position start)))
- (if (markerp end) (setq end (marker-position end)))
(or (and start end) (if zmacs-regions ;; rewritten for I18N3 snarfing
(error "The region is not active now")
(error "The mark is not set now")))
＠＠ -2018,15 +2016,14 ＠＠
(or global-mark-ring
(error "No global mark set"))
(let* ((marker (car global-mark-ring))
- (buffer (marker-buffer marker))
- (position (marker-position marker)))
+ (buffer (marker-buffer marker)))
(setq global-mark-ring (nconc (cdr global-mark-ring)
(list (car global-mark-ring))))
(set-buffer buffer)
- (or (and (>= position (point-min))
- (<= position (point-max)))
+ (or (and (>= marker (point-min))
+ (<= marker (point-max)))
(widen))
- (goto-char position)
+ (goto-char marker)
(switch-to-buffer buffer)))
diff -r 45b565af6128 -r 9a9e9993b412 lisp/wid-edit.el
--- a/lisp/wid-edit.el Fri Sep 28 11:00:54 2018 +0100
+++ b/lisp/wid-edit.el Mon Oct 01 00:42:55 2018 +0100
＠＠ -1553,8 +1553,7 ＠＠
widget-field-list (cons field widget-field-list))
(let ((from (car (widget-get field :field-extent)))
(to (cdr (widget-get field :field-extent))))
- (widget-specify-field field
- (marker-position from) (marker-position to))
+ (widget-specify-field field from to)
(set-marker from nil)
(set-marker to nil))
;; If the field is placed within the inactive zone, deactivate it.
diff -r 45b565af6128 -r 9a9e9993b412 lisp/window-xemacs.el
--- a/lisp/window-xemacs.el Fri Sep 28 11:00:54 2018 +0100
+++ b/lisp/window-xemacs.el Mon Oct 01 00:42:55 2018 +0100
＠＠ -522,13 +522,13 ＠＠
(set-window-buffer window
(saved-window-buffer saved-window))
(set-window-start window
- (marker-position (saved-window-start-marker saved-window))
+ (saved-window-start-marker saved-window)
t)
(if (markerp (saved-window-point-marker saved-window))
(set-window-point window
- (marker-position (saved-window-point-marker saved-window))))
+ (saved-window-point-marker saved-window)))
(set-marker (mark-marker t buffer)
- (marker-position (saved-window-mark-marker saved-window))
+ (saved-window-mark-marker saved-window)
buffer)
(if (not (eq buffer (window-configuration-current-buffer configuration)))
(goto-char (window-point window) buffer)))))
diff -r 45b565af6128 -r 9a9e9993b412 man/ChangeLog
--- a/man/ChangeLog Fri Sep 28 11:00:54 2018 +0100
+++ b/man/ChangeLog Mon Oct 01 00:42:55 2018 +0100
＠＠ -1,3 +1,10 ＠＠
+2018-10-01 Aidan Kehoe <kehoea(a)parhasard.net>
+
+ * lispref/compile.texi (Different Behavior):
+ Mention the unfortunate algorithmic complexity of
+ #'marker-position when cautioning about the behaviour of (+ MARKER
+ 0).
+
2018-09-02 Aidan Kehoe <kehoea(a)parhasard.net>
* cl.texi (Time of Evaluation): Use the new-style
diff -r 45b565af6128 -r 9a9e9993b412 man/lispref/compile.texi
--- a/man/lispref/compile.texi Fri Sep 28 11:00:54 2018 +0100
+++ b/man/lispref/compile.texi Mon Oct 01 00:42:55 2018 +0100
＠＠ -1097,8 +1097,11 ＠＠
If you're trying to use ＠samp{(+ ＠var{object} 0)} to convert
＠var{object} to integer, consider using an explicit conversion function,
which is clearer and guaranteed to work.
-Instead of ＠samp{(+ ＠var{marker} 0)}, use ＠samp{(marker-position ＠var{marker})}.
Instead of ＠samp{(+ ＠var{char} 0)}, use ＠samp{(char-int ＠var{char})}.
+Instead of ＠samp{(+ ＠var{marker} 0)}, you can write
+＠samp{(marker-position ＠var{marker})}, but this has its own efficiency
+problems. You many not need to convert from a marker at all, since most
+of the primitives convert automatically; test your code!
＠end itemize
For maximal equivalence between interpreted and compiled code, the
diff -r 45b565af6128 -r 9a9e9993b412 src/ChangeLog
--- a/src/ChangeLog Fri Sep 28 11:00:54 2018 +0100
+++ b/src/ChangeLog Mon Oct 01 00:42:55 2018 +0100
＠＠ -1,3 +1,9 ＠＠
+2018-10-01 Aidan Kehoe <kehoea(a)parhasard.net>
+
+ * marker.c (Fmarker_position):
+ Advise not to use this function in its docstring; give an example
+ of a restricted use case where it is reasonable.
+
2018-09-17 Aidan Kehoe <kehoea(a)parhasard.net>
* buffer.c (Fline_number):
diff -r 45b565af6128 -r 9a9e9993b412 src/marker.c
--- a/src/marker.c Fri Sep 28 11:00:54 2018 +0100
+++ b/src/marker.c Mon Oct 01 00:42:55 2018 +0100
＠＠ -136,8 +136,22 ＠＠
}
DEFUN ("marker-position", Fmarker_position, 1, 1, 0, /*
-Return the position MARKER points at, as a character number.
+Return the buffer position to which MARKER points, as a fixnum.
+
Return `nil' if marker doesn't point anywhere.
+
+Usually there is no need to call this function; if you are using
+marker positions in arithmetic or comparing them, markers are
+converted automatically as needed. Markers are stored internally as
+byte, not character positions, so in the worst case scenario
+`marker-position' is O(N) on the (possibly large) position in the
+buffer, and much of the time the C code can avoid this entirely given
+its knowledge of the relationship between byte and character
+positions.
+
+One of the few use cases for this function is when saving a buffer
+offset to an external file, when the integer value does need to be
+generated.
*/
(marker))
{
--
‘As I sat looking up at the Guinness ad, I could never figure out /
How your man stayed up on the surfboard after forty pints of stout’
(C. Moore)