diff options
| -rw-r--r-- | doc/lispref/windows.texi | 21 | ||||
| -rw-r--r-- | lisp/window.el | 25 |
2 files changed, 39 insertions, 7 deletions
diff --git a/doc/lispref/windows.texi b/doc/lispref/windows.texi index 55d90bd5d0..386584bf9e 100644 --- a/doc/lispref/windows.texi +++ b/doc/lispref/windows.texi @@ -4349,6 +4349,27 @@ window when it deletes the window passed to it as argument. The fourth element is the buffer whose display caused the creation of this parameter. @code{quit-restore-window} deletes the specified window only if it still shows that buffer. + +@item @code{min-margins} +The value of this parameter is a cons cell whose @sc{car} and @sc{cdr}, +if non-@code{nil}, specify the minimum values (in columns) for the left +and right margin of this window. When present, Emacs will use these +values instead of the actual margin widths for determining whether a +window can be split or shrunk horizontally. + +Emacs never auto-adjusts the margins of any window after splitting or +resizing it. It is sole responsibility of the application that has set +this parameter to adjust the margins of this window as well as those of +any new window that inherits this window's margins due to a split. +Both, @code{window-configuration-change-hook} and +@code{window-size-change-functions} (@pxref{Window Hooks}), should be +employed for this purpose. + +This parameter was introduced in Emacs version 25.1 to support +applications that use large margins to center buffer text within a +window and should be used, with due care, exclusively by those +applications. It might be replaced by an improved solution in future +versions of Emacs. @end table There are additional parameters @code{window-atom} and @code{window-side}; diff --git a/lisp/window.el b/lisp/window.el index f7a547b915..8505bef6b1 100644 --- a/lisp/window.el +++ b/lisp/window.el @@ -1383,10 +1383,21 @@ ignore width restrictions for WINDOW." (let* ((char-size (frame-char-size window t)) (fringes (window-fringes window)) (margins (window-margins window)) + ;; Let the 'min-margins' parameter override the actual + ;; widths of the margins. We allow any number to + ;; replace the values specified by `window-margins'. + ;; See bug#24193 for the rationale of this parameter. + (min-margins (window-parameter window 'min-margins)) + (left-min-margin (and min-margins + (numberp (car min-margins)) + (car min-margins))) + (right-min-margin (and min-margins + (numberp (cdr min-margins)) + (cdr min-margins))) (pixel-width (+ (window-safe-min-size window t t) - (* (or (car margins) 0) char-size) - (* (or (cdr margins) 0) char-size) + (* (or left-min-margin (car margins) 0) char-size) + (* (or right-min-margin(cdr margins) 0) char-size) (car fringes) (cadr fringes) (window-scroll-bar-width window) (window-right-divider-width window)))) @@ -4774,7 +4785,7 @@ frame. The selected window is not changed by this function." (window-sizable-p parent (- (+ new-pixel-size divider-width)) horizontal (setq ignore 'preserved) t)) - (error "Window %s too small for splitting (1)" parent))) + (error "Window %s too small for splitting" parent))) ((and (> (+ new-pixel-size divider-width (window-min-size window horizontal nil t)) old-pixel-size) @@ -4783,7 +4794,7 @@ frame. The selected window is not changed by this function." window horizontal (setq ignore 'preserved) t)) old-pixel-size)) ;; SIZE unspecified, no resizing. - (error "Window %s too small for splitting (2)" window)))) + (error "Window %s too small for splitting" window)))) ((and (>= pixel-size 0) (or (>= pixel-size old-pixel-size) (< new-pixel-size @@ -4791,7 +4802,7 @@ frame. The selected window is not changed by this function." ;; SIZE specified as new size of old window. If the new size ;; is larger than the old size or the size of the new window ;; would be less than the safe minimum, signal an error. - (error "Window %s too small for splitting (3)" window)) + (error "Window %s too small for splitting" window)) (resize ;; SIZE specified, resizing. (unless (or (window-sizable-p @@ -4801,13 +4812,13 @@ frame. The selected window is not changed by this function." parent (- (+ new-pixel-size divider-width)) horizontal (setq ignore 'preserved) t)) ;; If we cannot resize the parent give up. - (error "Window %s too small for splitting (4)" parent))) + (error "Window %s too small for splitting" parent))) ((or (< new-pixel-size (window-safe-min-pixel-size window horizontal)) (< (- old-pixel-size new-pixel-size) (window-safe-min-pixel-size window horizontal))) ;; SIZE specification violates minimum size restrictions. - (error "Window %s too small for splitting (5)" window))) + (error "Window %s too small for splitting" window))) (window--resize-reset frame horizontal) |