Re: Spreadsheet display mode

[Richard Stallman <rms@gnu.org>]

    I wrote something called "cell-mode" that seems similar to what you
    describe. It holds a grid of cells whose "labels" are
    application-defined strings with text properties, and draws them to a
    buffer.

In your design, the buffer holds the text as it is displayed,
and the real underlying text is somewhere else.

In the design I have in mind, the real, underlying text is in the
buffer, so editing operates on the underlying text.  The columnar
display form would NOT be in the buffer.  It would be generated
inside the display code under the control of this new feature.

Maybe we could combine the two ideas using a hidden buffer.  Your code
could operate on the user-visible buffer, generating text in another
buffer, and redisplay would use part of that other buffer in place of
parts of the user-visible buffer.

With this design, the C code would be more general, and the columnar
part of it would be entirely in Lisp.

In difference to your current design, the data that the user edits
would be in the buffer.  Ordinary editing commands would mostly still
work.

What do you think?