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Message-ID:  <4E7C222D.5000700@morningstar2.co.uk>
Date:         Fri, 23 Sep 2011 07:07:41 +0100
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From: Joseph Wright <joseph.wright@MORNINGSTAR2.CO.UK>
Subject: Re: \interlinepenalties
To: LATEX-L@listserv.uni-heidelberg.de
In-Reply-To:  <CANQYN6z=PF-FutdhLC0EJ=VCgHnt8czXW0KgQ_-iE0giSxF+NQ@mail.gmail.com>
Precedence: list
Status: R

On 22/09/2011 22:44, Bruno Le Floch wrote:
>> What it seems is needed is an interface that makes sense, i.e. which
>> separates out:
>>
>>   1) The general interline penalty
>>   2) The penalty for lines(s) at the start of the paragraph as a whole
>>   3) The penalty for lines(s) at the end of the paragraph as a whole
>>   4) The penalty for line(s) before display math
>>   5) The penalty for line(s) after display math
>>   6) Additional penalties between arbitrary lines
>>
>> or some such structure. This will require a bit of thought, as it means
>> synchronising the various primitives in an ordered way.
> 
> I'm afraid (3) doesn't exist (not sure). It would be
> \the\interlinepenalties <length>-k, where <length> is the number of
> lines in the paragraph.

No, \widowpenalties applies only at the end of the paragraph as a whole,
not at the end of the partial paragraph. The \widowpenalties and
\displaywidowpenalties cover cases (3) and (4) in a clear manner
(additivity, of course, with \interlinepenalt(y|ies).

I have an overall idea now on what is needed!
-- 
Joseph Wright