Re: display-buffer-overriding-action

[Chong Yidong]

Stefan Monnier <address@hidden> writes:

>> If the majority of non-trivial calls to display-buffer are not going to
>> use the ACTION argument, that is a waste of the ACTION argument.
>
> Agreed.  I see no evidence that we're heading this way.

I don't think we are convincing each other.  I guess we can keep the
current system, but let me make sure I understand your position:

- Interactive and non-interactive calls to switch-to-buffer,
  switch-to-buffer-other-window, and switch-to-buffer-other-frame shall
  override d-b-alist.  (This includes calls from commands in the Emacs
  sources.)

- To do this, s-t-buffer etc should let-bind d-b-overriding-action,
  instead of using ACTION as they currently do.

- This means that d-b-alist can't be used to tell Emacs "when I call
  s-t-buffer(-other-*) for this buffer, do this action instead".
  AFAICT there would be no way to do this except advice.

- If d-b-overriding-action is meant for use by s-t-b and co, then it
  should be a defvar, not a defcustom.

Is this accurate?

> That's the reason why we have the ACTION argument: so non-trivial
> users of display-buffer can pass their preference without imposing it
> on the user (because the user can override it in d-b-alist).

Any example in mind?  Note that if s-t-buffer etc are changed to use
d-b-overriding-action, there will be zero uses of the ACTION argument in
the Emacs source tree.  But can you point to the prospect of any uses in
the future?