bug#51176: eww switch buffer by title

[Protesilaos Stavrou <info@protesilaos.com>]

On 2021-10-16, 07:16 +0300, Protesilaos Stavrou <info@protesilaos.com> wrote:

> On 2021-10-15, 20:59 +0100, Jose Antonio Ortega Ruiz <jao@gnu.org> wrote:
>
>> On Fri, Oct 15 2021, Lars Ingebrigtsen wrote:
>>
>>> Jose Antonio Ortega Ruiz <jao@gnu.org> writes:
>>>
>>>> Since you went for the complex config, and additional option i'd find
>>>> useful for the ewww rename "flag" would be a string that specifies the
>>>> format to use once the title/url part has been computed.  So one can set
>>>> it to, say, "eww: %s", or whatever. I know that that use case is already
>>>> covered by the possibility of specifying a function, but having to
>>>> duplicate the default function just to change the final format string
>>>> feels a bit overkill (and i suspect changing the format is going to be a
>>>> very common reason to opt for a function call).
>>>
>>> I think it's best to leave that sort of flexibility to the function
>>> option -- there's too many ways users may want to customise this.
>>
>> but, 43.45% of users will simply want to change the format and get rid
>> of "# eww" at the end to see more of the title! :)
>>
>> specifying a format string is extremely common in many packages out
>> there for things like this, and is, in my opinion, much more
>> user-friendly: to change that format with a function, one has to study
>> eww's api for obtaining title and url, and write a non-trivial piece of
>> elisp, probably (although admittedly not necessarily) outside the
>> customization interface.
>>
>> in other words, i find the format string option as natural and common as
>> the nil and t ones (which, in a way, are also redundant and could be
>> removed, since it's trivial to write a function for them).
>>
>> but i'm probably exaggerating: people will simply copy and paste the
>> relevant piece of elisp in their init files and call it a day.  so i'll
>> stop the bike-shedding now :)
>
> How about we add a sample function in the doc string?  That would give
> users all the information they need to get started, no?

Sorry, I sent the wrong version...  I meant this function:

    (defun my-eww-rename-buffer ()
      (when (eq major-mode 'eww-mode)
        (when-let ((string (or (plist-get eww-data :title)
                               (plist-get eww-data :url))))
          (format "*%s*" string))))

And we edit this doc string:

    (defcustom eww-auto-rename-buffer nil
      "Automatically rename EWW buffers once the page is rendered.

    When nil, do not rename the buffer.  With a non-nil value
    determine the renaming scheme, as follows:

    - `title': Use the web page's title.
    - `url': Use the web page's URL.
    - a function's symbol: Run a user-defined function that returns a
      string with which to rename the buffer.  Sample of a
      user-defined function:

        (defun my-eww-rename-buffer ()
          (when (eq major-mode 'eww-mode)
            (when-let ((string (or (plist-get eww-data :title)
                                   (plist-get eww-data :url))))
              (format \"*%s*\" string))))

    The string of `title' and `url' is always truncated to the value
    of `eww-buffer-name-length'."
      :version "29.1"
      :type '(choice
              (const :tag "Do not rename buffers (default)" nil)
              (const :tag "Rename buffer to web page title" title)
              (const :tag "Rename buffer to web page URL" url)
              (function :tag "A user-defined function to rename the buffer"))
      :group 'eww)

-- 
Protesilaos Stavrou
https://protesilaos.com