Re: Emacs design and architecture (was: Shrinking the C core)

[Richard Stallman]

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  > They are all well known.  And they aren't ideas, just main design
  > features of Emacs which we found restrictive in some aspects:

  >   . "buffer with gap" for storing buffer text
  >   . "mark and sweep" GC
  >   . basic single-threaded MVC architecture
  >   . display engine design around the rectangular canvas model and
  >     on-the-fly layout decisions

These are internal design decisions.
The last one does relate to some user-level features
such as data in the buffer.  The first three don't.

So I don't see these as being related to simplicity
that benefits the users.

Changes in those design aspects could make development and maintenance
harder and/or more likely to go wrong.  For example, some other kinds
of GC could impose constraints on development that could make writing
C code for Emacs error-prone.  But they won't complicate _use_ of
Emacs as long as we avoid those errors.

A more complex and powerful data structure in the buffer is something
I would like to see.  I would like it to enable TeX-style formatting
of text for display.

However, finding a good design for this will be a hard job, I think.
We would want it to facilitate redisplay and also be easy for editing.
It needs to support editing primitives of the traditional Emacs kind,
which treat text as a sequence somehow (even if not the same as now),
and editing primitives that operate on the structure and make them
convenient.

All four of those directions are basically independent.
Any one could be done with or without the others.


-- 
Dr Richard Stallman (https://stallman.org)
Chief GNUisance of the GNU Project (https://gnu.org)
Founder, Free Software Foundation (https://fsf.org)
Internet Hall-of-Famer (https://internethalloffame.org)