Re: display-buffer-alist simplifications

[Chong Yidong]

Eli Zaretskii <address@hidden> writes:

> OTOH, we have the example of frame parameters alist, which supports
> merging with the default-frame-alist, is quite self-explanatory, and
> works quite well in practice, AFAIK.
>
> So why wouldn't display-buffer-alist be useful as an alist as well,
> without any need for a plist?

One difference is that frame parameters don't interact with one another.
Each entry in default-frame-alist overrides any corresponding entry in
initial-frame-alist, and is overridden in turn by any corresponding
entry in window-system-default-frame-alist.

Another difference is that in default-frame-alist, each stored value
(i.e. the cdrs of an alist entry) has a straightforward meaning: it is a
value of a frame parameter.  In display-buffer-alist, each stored value
is a _list_ of specifiers, and each specifier has its own no-obvious
meaning.  For example, in the specifier

   (reuse-window nil nil nil)

each of the `nil's means something different, and you have to look up to
docstring to figure out what it is.