Re: Beginingless paragraphs

[Richard M. Stallman]

Overall, the change is good, but there are many details that should be
done differently.

    I've worked out just what's been bugging me, and that's the definition of
    `paragraph-start':  It suggests (though it doesn't quite explicitly say)
    that paragraph-start matches the start of _every_ paragraph.  This isn't
    true - any line following a separator line is the start of a paragraph.

That is true, but paragraph-start does have a match at or just before
the start of every paragraph.  THat's because it is supposed to match
separator lines, too.

    OK, here's my first shot at a patch:  As a matter of interest, what's
    this node doing in "Searching and Matching"?

Because that's where regexps are.

    !   This section describes the regular expressions Emacs uses to
    ! recognize pages, paragraphs, and sentences.  By setting these
    ! variables appropriately, the Elisp programmer can control the precise

Please write "Emacs Lisp".

    ! @table @asis
    ! @cindex page
    ! @item Pages
      @defvar page-delimiter
    ! This is the regular expression describing line-beginnings that
    ! separate pages.  The default value is @code{"^\014"} (i.e.,

Using @defvar inside of @table is a peculiar thing to do.
It may look bad in TeX or in Makeinfo.

    ! This is the regular expression describing line-beginnings that

"Describing" is vague; what it does is match them.

    !   Buffers divide into @dfn{paragraphs}, 

That is a strange way to put it.  It sounds like you're saying that
buffers actually split up.  It would be better to make this
parallel to the info about pages.

    ! normally don't address@hidden is possible for a blank line to be
    ! both the last line of one paragraph and the first line of the next.}.

Are you sure?  I don't think so.  A blank line would normally
be a separator line, not the first or last line of any paragraph.

    ! This regular expression recognizes a line which starts a paragraph
    ! when the previous line is not a separator.  It need only match some
    ! portion beginning at the line's left margin (@pxref{Margins for
    ! Filling}), not the whole line.  It must also be set up to recognize a
    ! separator line.

I think this way of putting it is less clear than the the current way:
that it should match lines that either start or separate paragraphs.

    + The two variant forms of paragraph breaks are:
    + 
    + @table @asis
    + @item Paragraph break without separator lines
    + Any line, apart from a separator line, which @code{paragraph-start}
    + recognizes starts a new paragraph.
    + 
    + @item Paragraph break with separator lines
    + One or more separator lines split the old paragraph from the new one.
    + Whether @code{paragraph-start} would also recognize the first line of
    + the new paragraph is irrelevant.
    + @end table

Itemizing these two is a good idea (but you should use @itemize, not
@table).  However, calling them "variant forms" is confusing.
I suggest calling them "two ways that paragraphs can be separated".
Also I suggest swapping them, because the first one is the usual case
and the simplest case to understand.

    + 
    +   As a heuristic feature,

The phrase "heuristic feature" does not make sense to me.

                                if a line tentatively recognized as the
    + start of a paragraph follows a whitespace line, the whitespace line
    + becomes the start of the paragraph instead.

That is a confusing way to put it.  It's clearer to say "is included in the
paragraph" than "becomes the start of the paragraph".