-.\" $Id: mandoc_char.7,v 1.62 2015/03/30 16:06:14 schwarze Exp $
+.\" $Id: mandoc_char.7,v 1.64 2017/02/05 21:41:21 schwarze Exp $
.\"
.\" Copyright (c) 2003 Jason McIntyre <jmc@openbsd.org>
.\" Copyright (c) 2009, 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
.\"
-.Dd $Mdocdate: March 30 2015 $
+.Dd $Mdocdate: February 5 2017 $
.Dt MANDOC_CHAR 7
.Os
.Sh NAME
.Ss Dashes and Hyphens
In typography there are different types of dashes of various width:
the hyphen (-),
-the minus sign (\-),
+the minus sign (\(mi),
the en-dash (\(en),
and the em-dash (\(em).
.Pp
lorry-driver
.Ed
.Pp
+If a word on a text input line contains a hyphen, a formatter may decide
+to insert an output line break after the hyphen if that helps filling
+the current output line, but the whole word would overflow the line.
+If it is important that the word is not broken across lines in this
+way, a zero-width space
+.Pq Sq \e&
+can be inserted before or after the hyphen.
+While
+.Xr mandoc 1
+never breaks the output line after hyphens adjacent to a zero-width
+space, after any of the other dash- or hyphen-like characters
+represented by escape sequences, or after hyphens inside words in
+macro arguments, other software may not respect these rules and may
+break the line even in such cases.
+.Pp
+Some
+.Xr roff 7
+implementations contains dictionaries allowing to break the line
+at syllable boundaries even inside words that contain no hyphens.
+Such automatic hyphenation is not supported by
+.Xr mandoc 1 ,
+which only breaks the line at whitespace, and inside words only
+after existing hyphens.
+.Pp
The mathematical minus sign is used for negative numbers or subtraction.
It should be written as
-.Sq \e- :
+.Sq \e(mi :
.Bd -unfilled -offset indent
-a = 3 \e- 1;
-b = \e-2;
+a = 3 \e(mi 1;
+b = \e(mi2;
.Ed
.Pp
The en-dash is used to separate the two elements of a range,
.Fl T Ns Cm ascii ,
the
\e(ss, \e(nm, \e(nb, \e(nc, \e(ib, \e(ip, \e(pp, \e[sum], \e[product],
-\e[coproduct], \e(gr, \e(\-h, and \e(a. special characters render
+\e[coproduct], \e(gr, \e(-h, and \e(a. special characters render
differently between mandoc and groff.
.It
In