Re: better glyph for U+00B0 (DEGREE SIGN)

[Gavin Smith]

On Fri, Nov 11, 2022 at 11:48:47AM +0100, Patrice Dumas wrote:
> On Fri, Nov 11, 2022 at 08:47:32AM +0000, Werner LEMBERG wrote:
> > 
> > [texinfo.tex 2022-11-07.17]
> > 
> > 
> > I suggest to change the mapping for U+00B0 (DEGREE SIGN) to use
> > `@textdegree{}`.
> > 
> > ```
> > \input texinfo
> > 
> > @code{45°}
> > 
> > @code{45@textdegree{}}
> > 
> > @bye
> > ```
> 
> It is better to be consistent in my opinion.  Here is a proposed patch,
> it does not use @textdegree but leads to the same output as @textdegree{}.
> It fails in @math{}, but the preceding mapping also failed in @math.

Note that there are also definitions for Latin-1 and Latin-2 which already
use @textdegree.

I don't know what the original reasoning was behind using \ringaccent.

A fixed width degree sign can be got with a little difficulty.  It's
only worth doing this if somebody is actually using degree signs in
a fixed width context - I don't have much interest in fixing this for all of
the character definitions.

Please test the patch at the end of this mail.  Sample input:

45°

@code{45°}

45@textdegree{}

@code{45°}

@math{45°}

@example
aaaaaa
45°aaa
aaaaaa
@end example


diff --git a/doc/texinfo.tex b/doc/texinfo.tex
index b1bf41ff56..2e4b4a9e65 100644
--- a/doc/texinfo.tex
+++ b/doc/texinfo.tex
@@ -3691,7 +3691,9 @@ $$%
 
 % @textdegree - the normal degrees sign.
 %
-\def\textdegree{$^\circ$}
+\def\textdegree{\ifusingtt
+  {\hbox to \fontdimen2\font {\ensuremath{^\circ}\hfil}}%
+  {\ensuremath{^\circ}}}
 
 % Laurent Siebenmann reports \Orb undefined with:
 %  Textures 1.7.7 (preloaded format=plain 93.10.14)  (68K)  16 APR 2004 02:38
@@ -10063,7 +10065,7 @@ directory should work if nowhere else does.}
   \gdefchar^^ae{\v Z}
   \gdefchar^^af{\dotaccent Z}
   %
-  \gdefchar^^b0{\textdegree{}}
+  \gdefchar^^b0{\textdegree}
   \gdefchar^^b1{\ogonek{a}}
   \gdefchar^^b2{\ogonek{ }}
   \gdefchar^^b3{\l}
@@ -10486,7 +10488,7 @@ directory should work if nowhere else does.}
   \DeclareUnicodeCharacter{00AE}{\registeredsymbol{}}%
   \DeclareUnicodeCharacter{00AF}{\={ }}%
   %
-  \DeclareUnicodeCharacter{00B0}{\ringaccent{ }}%
+  \DeclareUnicodeCharacter{00B0}{\textdegree}
   \DeclareUnicodeCharacter{00B1}{\ensuremath\pm}%
   \DeclareUnicodeCharacter{00B2}{$^2$}%
   \DeclareUnicodeCharacter{00B3}{$^3$}%