Re: [Groff] bad QE in -ms

[Doug McIlroy]

>> The -ms macro QE typically draws a misleading diagnostic, "unbalanced QE".
>> This breaks old documents that expect QP-QE (quoted paragraph) to narrow
>> the text and then restore it. The groff QE does not restore.
>>
>> In fact, QE is aliased to RE, which means it will cause other trouble
>> for a quoted paragraphs inside an RS-RE relative indent.
>>
>> I guess the rationale for deviating from previous practice was to make
>> quoted paragraphs like other kinds of paragraph, which don't have end
>> macros.

> That's the way I'd always thought it worked. QP sets a block quoted paragraph,
> and the next LP or PP resets the margins to default.

> Perhaps it would be better to:

> .als QE nop

> So it's silently ignored.

Unfortunately, nop doesn't fix things very well, as these examples show:

Bad case I: 
        .PP
        A display quote occurs
        .QP
        Like this
        .QE
        in the middle of what the author wrote as
        one logical paragraph.
        .PP
        Then groff -ms would add the tail of that paragraph 
        to the quote.

Bad case II:
        .KF
        .PS
        #Here's a figure
        .PE
        .QP
        And its caption.
        .QE
        .KE
        .PP
        The following paragraph begins well enough, but if the
        figure gets floated to the next page, then the caption
        will run into the body text on that page

.als QE LP isn't perfect; one can invent cases where the LP
adds extra vertical space. But in general too much space is
better than none at all. Notice, though, that it won't hurt
any document that uses the latter-day (no QE) convention.