RE: How to add property for a buffer object

["Drew Adams" <drew.adams@oracle.com>]

> > You can use `get' and `put' on the symbol that is the value 
> > of variable `major-mode'.
> 
> I don't think this would help because I need to attach 
> something to the buffer, not all the buffers in the major-mode.

Or you could keep track of which buffers in the mode you care about this way.
IOW, work with a list of buffers instead of setting and getting a property for
each of those buffers.

> > Or you can simply make some variable buffer-local for a given mode.
> 
> Yes, I think this would work, but I then have to create a 
> variable for this, have no idea why Emacs doesn't allow
> assigning property to the buffer object itself, just like
> assigning property to a symbol.

Emacs Lisp has:

* symbol properties for symbols

* text properties for buffer text and strings

* overlay properties for overlays (which apply to buffers, and by extension to a
buffer's window)

* button properties for buttons

That's about it, IIRC.  But usually other Lisp objects that you might want to
assign a property to are somehow associated with one or more of those things, so
you can just assign the property to the associated thing (e.g., to a symbol).

For a buffer, as an alternative to a buffer-local variable or a list of affected
buffers, you could put a property on a symbol whose name is the same as the
buffer name.  Or you could put a text property on a string that is `string=' to
the buffer name.  Or if you can depend on some of the buffer text remaining the
same, you could put a text property on some buffer position (e.g. (point-min)).

> > Test something specific to the buffer or its mode (see above).
> > Or just use a prefix arg (and test that).
> 
> I'm sure this would work, but I'm still not happy with having 
> to do it this way.

> Maybe the ultimate solution is to fix the `refill-mode' itself
> so that I can alway have it turned on (tired of having to hit "M-q" almost 
> all the time).

I don't use `refill-mode', but the doc string says it is a (buffer-local) minor
mode.  (I guess there is no globalized equivalent, but you could define one if
you needed it.)

> The major problem with `refill-mode' however, is that it intercepts
> the "fill-function" therefor was not able to handle refilling 
> properly in org-mode, especially, it would mess up org tables.
> Also, if you have `refill-mode' turned on, you will never be able
> to break a paragraph into two by hitting <RET> while
> the point is in the middle of the paragraph.

Sounds like there should be a bug report or enhancement request in there
somewhere. ;-)  `M-x report-emacs-bug'.

> On the other hand, the `auto-fill-mode' never "auto-fill" when
> inserting text in the middle of a line, because of this, I have
> to hit "M-q" all the time. Do you know of any other way
> to really handle "auto-fill" property?

No, I'm probably not the right one to ask.  But hopefully someone else will have
a suggestion.  I use `M-q' and `C-M-q' (e.g. in Lisp code).

There are also other fill commands, which operate on multiple paragraphs in the
region: `fill-region', `fill-individual-paragraphs', and
`fill-nonuniform-paragraphs'.  When one of them does what you want, you might be
able to use it in place of several uses of `M-q'.