Re: comint-prompt-regexp

[Luc Teirlinck <teirllm@dms.auburn.edu>]

Things seem to be a little bit more complex still.  From the
documentation in the Emacs manual, it would appear that the intent is
that a paragraph in a Shell buffer should always consist of a complete
"prompt-input-output" group.  But, even when
`comint-use-prompt-regexp-instead-of-fields' is non-nil, blank lines
count as paragraph separators, even though not as paragraph starters.
The docstring of paragraph-start says that this is something that
should never happen:

  paragraph-start's value is "\f\\|[	]*$"

  *Regexp for beginning of a line that starts OR separates paragraphs.
  This regexp should match lines that separate paragraphs
  and should also match lines that start a paragraph
  (and are part of that paragraph).

To correct this, we could either set paragraph-separate to
comint-prompt-regexp too, or we could set paragraph-start to:
(concat paragraph-separate "\\|" comint-prompt-regexp)

The latter would yield the exact described behavior.

The problem for Ielm is exactly the same as for Shell Mode.
Paragraphs commands in Inferior Lisp mode currently do not do anything
useful, but for consistency (and convenience) they should behave the
same as in Shell mode and Ielm.  Maybe the paragraph commands should
behave consistently in _all_ Comint buffers, and hence have a default
implementation in comint.el.

Sincerely,

Luc.