[groff] 04/11: [man pages]: Reduce misuse of "hyphen-minus".

[G. Branden Robinson]

gbranden pushed a commit to branch master
in repository groff.

commit b246e358754acd9e6331cb641dd408541945257c
Author: G. Branden Robinson <g.branden.robinson@gmail.com>
AuthorDate: Sun May 9 12:33:36 2021 +1000

    [man pages]: Reduce misuse of "hyphen-minus".
    
    * man/groff.7.man: Refer to "minus sign" instead of "hyphen-minus" when
      referring to keyboard cap engraving.
    * man/groff_char.7.man: In groff, and in troff all the way back to its
      inception, "\-" was only ever and always a minus sign.  (Observe how
      the man pages were changed from Version 3 to Version 4; cf.
        https://minnie.tuhs.org/cgi-bin/utree.pl?file=V3/man/man1/ls.1
      when troff did not yet exist, and
        https://minnie.tuhs.org/cgi-bin/utree.pl?file=V4/man/man1/ls.1
      when it did.  The Unix option dash changed from a simple "-" in man
      pages to a string, "\*-".  (A string of the same name for the same
      purpose survives in the ms package to this day.)
    
      Be more explicit when giving advice for best results.  Note existence
      of \[mi].  Prevent perverse inference that groff doesn't support \(em.
    
    We now talk about "hyphen-minus" only where we have to: in groff_char(7)
    and the man macro package.
---
 man/groff.7.man      |  2 +-
 man/groff_char.7.man | 19 ++++++++++++++-----
 2 files changed, 15 insertions(+), 6 deletions(-)

diff --git a/man/groff.7.man b/man/groff.7.man
index bf3e973..c9d12e9 100644
--- a/man/groff.7.man
+++ b/man/groff.7.man
@@ -525,7 +525,7 @@ the (double) quotation mark
 .RB ( \[dq] ),
 the apostrophe
 .RB ( \[aq] ),
-the hyphen-minus
+the minus sign
 .RB ( \- ),
 the backslash
 .RB ( \[rs] ),
diff --git a/man/groff_char.7.man b/man/groff_char.7.man
index 10eb281..561c611 100644
--- a/man/groff_char.7.man
+++ b/man/groff_char.7.man
@@ -8,7 +8,7 @@ groff_char \- GNU roff special character and glyph repertoire
 .\" Legal Terms
 .\" ====================================================================
 .\"
-.\" Copyright (C) 1989-2020 Free Software Foundation, Inc.
+.\" Copyright (C) 1989-2021 Free Software Foundation, Inc.
 .\"
 .\" This file is part of groff (GNU roff), which is a free software
 .\" project.
@@ -360,7 +360,7 @@ Keycap      Appearance and meaning  Special character and 
meaning
 _
 "      " neutral double quote  \f[B]\[rs][dq]\f[] neutral double quote
 \[aq]  \[cq] closing single quote      \f[B]\[rs][aq]\f[] neutral apostrophe
-\-     - hyphen        \f[B]\[rs]\-\f[] or \f[B]\[rs][\-]\f[] hyphen-minus
+\-     - hyphen        \f[B]\[rs]\-\f[] or \f[B]\[rs][\-]\f[] minus sign
 \[rs]  (escape character)      \f[B]\[rs]e\f[] or \f[B]\[rs][rs]\f[] reverse 
solidus
 \[ha]  \[u02C6] modifier circumflex    \f[B]\[rs](ha\f[] 
circumflex/caret/\[lq]hat\[rq]
 \[ga]  \[oq] single opening quote      \f[B]\[rs](ga\f[] grave accent
@@ -384,7 +384,9 @@ dashes of varying widths.
 .
 For best results in
 .IR groff ,
-use the character in input without an escape
+use the
+.RB \[lq] \- \[rq]
+character in input without an escape
 .I only
 to mean a hyphen,
 as in the phrase \[lq]long-term\[rq].
@@ -398,10 +400,17 @@ in
 .I groff
 if you find it helps the clarity of the source document).
 .
+(Another minus sign,
+for use in mathematical equations,
+is available as
+.BR \[rs][mi] ).
+.
 AT&T
 .I troff
 supported em-dashes as
-.BR \[rs](em .
+.BR \[rs](em ,
+as does
+.IR groff .
 .
 .
 .P
@@ -648,7 +657,7 @@ the uninterpreted leader escape sequence.
 By default,
 .I groff
 defines a single glyph name of length one,
-namely the hyphen-minus,
+namely the minus sign,
 which can be accessed as either
 .B \[rs]\-
 or