Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!csd4.milw.wisc.edu!cs.utexas.edu!uunet!mcvax!ukc!warwick!anduk!lee
From: lee@anduk.co.uk (Liam R. Quin)
Newsgroups: comp.text
Subject: Re: em-dashes
Message-ID: <28@nx32s.anduk.co.uk>
Date: 8 Jul 89 21:29:17 GMT
References: <65590@yale-celray.yale.UUCP> <65736@yale-celray.yale.UUCP>
Reply-To: lee@nx32s.UUCP (0000-Liam R. Quin)
Organization: Unixsys (UK) Ltd, Warrington, England
Lines: 59

Horne-Scott@cs.yale.edu (Scott Horne) writes:
> leichter@CS (Jerry Leichter) writes:
>> jwright@atanasoff.cs.iastate.edu (Jim Wright) writes...
>>  leichter@CS.YALE.EDU (Jerry Leichter (LEICHTER-JERRY@CS.YALE.EDU)) writes:

[various points about em dashes in fonts]

Hart's Rules for Compositors and Readers at the University Press, Oxford
(I have the 39th edition), has the following to say about dashes:
[p.43]	Em rules or dashes---in this and the next line an
	example is given---are often used to show that words
	enclosed between them are to be treated parenthetically.

An example is given.  They are considered by Hart's to be on the same
semantic level as (parentheses) and ... ellipses.

Also, [p.155] (d) indicates that the em dash and hyphen should be
treated in the same way as regards spacing.

Hart's does not give any special indication about breaking a line before or
after an em dash, although some publishers do have strong feelings on this
subject.  One might also conclude from p. 155 (d) that it is better to break
a line after a dash rather than before, but I have seen both practices used.

It is not usual to emply a space greater than a thin either side of an em
dash, at any rate in England, as far as I can tell.  There are a few books
where an en or word space is used, but these often turn out to have been
set by the author.

>I've seen en dashes with surrounding spaces used as em dashes, but that's not
>attractive, either.  Do it this way---and no other.
Hart's explicitly forbids this!  Also, there should be no dash after a colon;
so you can't do:-
that.

>> Finally, I'll confess that I personally put spaces around CMR em-dashes.  I
>> started off doing it without thinking - I just copied my normal ASCII conven-
>> tions without realizing what I was doing.  Later, I started wondering, and
>> checked some references.  (Curiously, I never noticed the line in the LaTeX-
>> book before.)  When all was said and done, however, em-dashes with spaces
>> around them just look cleaner and more open to me; em-dashes without spaces
>> look crowded.
>
>Then at least do this:
>	I want to use an em dash~--- right here.
Or, for some publishers,
>	I want to use an em dash ---~right here.

Perhaps you should train TeX to ignore the spaces, and to treat only the
appropriate end(s) of the --- as possible break points.  I don't know TeX
well enough to do this.

Lee (uunet!utai!anduk.uucp!lee)

-- 
Lee Russell Quin, Unixsys UK Ltd, The Genesis Centre, Birchwood,
Warrington, ENGLAND, WA3 7BH; Tel. +44 925 828181, Fax +44 925 827834
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