bug#8275: 24.0.50; Intro to Emacs Lisp Issue

[Stefan Monnier <monnier@iro.umontreal.ca>]

> Do you want to fix this, or shall I try?  The problem is that
> append-to-buffer now uses let* and with-current-buffer, so this might
> break the flow of the text.  At this point in the book, let* and
> with-current-buffer are not yet introduced.

Here are some thoughts:
- I don't think it's of any importance that the example code be
  identical to the currently used code.
- append-to-buffer might not be the best example since AFAICT copying
  text from one buffer to another is not a common operation and in most
  cases this is done via buffer-substring + insert (often with some
  processing on the string between the two) rather than with
  insert-buffer-substring which is a rarely used function.
- yes, I think the text would benefit from some rethink to try and present
  with-current-buffer in preference to set-buffer, but it's not
  a simple fix.


        Stefan