Re: I wish list-buffers used my current window when it listed my buffers

[Michael Heerdegen]

Eric Abrahamsen <eric@ericabrahamsen.net> writes:

> Rustom Mody <rustompmody@gmail.com> writes:
>
> > On Thursday, August 15, 2013 7:32:50 AM UTC+5:30, Jay Cotton wrote:
> >> I've always wished list-buffers used my current window when it
> >> listed my
> >> buffers. I don't know why, but this rubbed me the wrong way
> >> immediately when
> >> I learned the command, and I've never been able to shake it.
> >
> > Does this work?
> >
> > (add-to-list 'same-window-buffer-names "*Buffer List*")
>
> Hey I was just thinking something similar about the *Help* buffer: I
> often look up docs for functions and variables, and then end up TAB-bing
> to the source file link and hitting return to see the definition.
>
> I like that the *Help* buffer itself opens a new window, but once I've
> got that new window I want the source file in question to re-use it,
> rather than going back and clobbering the window I was in.
>
> That's not quite the same thing as the OP's question, but it seems like
> a close cousin. I eventually found `display-buffer-alist' (I'm on 24.3),
> but the docstring for that is as confusing as any emacs docs I've ever
> read.

`display-buffer-alist': yes, it's not easy, and the docstring is not a
tutorial.  Please read

  (info "(elisp) Display Action Functions")

where it is explained well.

> Has anyone accomplished what I'm after?

I'm afraid that the buffer switching function is hardcoded in the button
definition in help-mode.el:

--8<---------------cut here---------------start------------->8---
(define-button-type 'help-function-def
  :supertype 'help-xref
  'help-function (lambda (fun file)
                   (require 'find-func)
                   (when (eq file 'C-source)
                     (setq file
                           (help-C-file-name (indirect-function fun) 'fun)))
                   ;; Don't use find-function-noselect because it follows
                   ;; aliases (which fails for built-in functions).
                   (let ((location
                          (find-function-search-for-symbol fun nil file)))
                     (pop-to-buffer (car location)) ; <--------------------
                     (if (cdr location)
                         (goto-char (cdr location))
                       (message "Unable to find location in file"))))
  'help-echo (purecopy "mouse-2, RET: find function's definition"))
--8<---------------cut here---------------end--------------->8---

To change the behavior, you have to redefine the button, replacing
`pop-to-buffer' with your own function.

Personally, I use this:

--8<---------------cut here---------------start------------->8---
(with-eval-after-load 'help
  (define-button-type 'help-function-def
    :supertype 'help-xref
    'help-function (lambda (fun file)
                     (require 'find-func)
                     (when (eq file 'C-source)
                       (setq file
                             (help-C-file-name (indirect-function fun) 'fun)))
                     ;; Don't use find-function-noselect because it follows
                     ;; aliases (which fails for built-in functions).
                     (let ((location
                            (find-function-search-for-symbol fun nil file)))
                       (my-find-symbol-switch-to-buffer (car location))
                       (if (cdr location)
                           (goto-char (cdr location))
                         (message "Unable to find location in file"))))
    'help-echo (purecopy "mouse-2, RET: find function's definition")))
--8<---------------cut here---------------end--------------->8---

where `my-find-symbol-switch-to-buffer' does what I want (i use it also
for "find-func.el" stuff).


Michael.