1 files changed, 87 insertions, 56 deletions
diff --git a/tex/context/base/supp-mat.mkiv b/tex/context/base/supp-mat.mkiv
index f77ee3454..bc26611ae 100644
--- a/tex/context/base/supp-mat.mkiv
+++ b/tex/context/base/supp-mat.mkiv
@@ -51,27 +51,32 @@
 \let\normalstartimath  \Ustartmath
 \let\normalstopimath   \Ustopmath
 \let\normalstartdmath  \Ustartdisplaymath
-\let\normalstopdmath   \Ustopdisplaymath
-
+\let\normalstopdmath   \Ustopmath
 \def\normalmathaligntab{&} % \let\normalmathaligntab\aligntab does to work well in a let to & (a def works ok)
 
-\let\normalsuper       \Usuperscript       % obsolete
-\let\normalsuber       \Usubscript         % obsolete
-
-\let\startimath        \Ustartmath
-\let\stopimath         \Ustopmath
-\let\startdmath        \Ustartdisplaymath
-\let\stopdmath         \Ustopmath
+\let\normalsuper      \Usuperscript             % obsolete
+\let\normalsuber      \Usubscript               % obsolete
+\let\startimath       \Ustartmath               % obsolete, less safe
+\let\stopimath        \Ustopmath                % obsolete, less safe
+\let\startdmath       \Ustartdisplaymath        % obsolete, less safe
+\let\stopdmath        \Ustopmath                % obsolete, less safe
 
 \unexpanded\def\mathematics#1{\relax         \ifmmode#1\else\normalstartimath#1\normalstopimath\fi}
 \unexpanded\def\displaymath#1{\noindent      \ifmmode#1\else\normalstartdmath#1\normalstopdmath\fi}
 \unexpanded\def\inlinemath #1{\dontleavehmode\ifmmode#1\else\normalstartimath#1\normalstopimath\fi}
 \unexpanded\def\textmath   #1{\dontleavehmode\ifmmode#1\else\begingroup\everymath\emptytoks\normalstartimath#1\normalstopimath\endgroup\fi} % \mathsurround\zeropoint
 
-\let\m\mathematics
+\let\m\mathematics % unexpanded?
 
 \let\stopmathmode\relax
 
+% \unexpanded\def\startmathmode % cannot be used nested
+%   {\relax\ifmmode
+%      \let\stopmathmode\relax
+%    \else
+%      \normalstartimath\let\stopmathmode\normalstopimath
+%    \fi}
+
 \unexpanded\def\startmathmode % nested variant
   {\relax\ifmmode
      \begingroup
@@ -91,12 +96,7 @@
 %D
 %D An example of usage of the following can be found in the MathML module:
 
-\ifdefined\strc_formulas_start_formula \else
-    \def\strc_formulas_start_formula{\normalstartdmath}
-    \def\strc_formulas_stop_formula {\normalstopdmath }
-\fi
-
-\unexpanded\def\displaymathematics#1{\relax\ifmmode#1\else\strc_formulas_start_formula{}#1\strc_formulas_stop_formula\fi}
+\unexpanded\def\displaymathematics#1{\relax\ifmmode#1\else\dostartformula{}#1\dostopformula\fi}
 \unexpanded\def\inlinemathematics   {\dontleavehmode\mathematics}
 \unexpanded\def\automathematics     {\relax\ifhmode\expandafter\inlinemathematics\else\expandafter\displaymathematics\fi}
 
@@ -128,8 +128,7 @@
 \def\dimensionhalfspace {\,}
 
 \unexpanded\def\dimension#1%
-  {\pushmacro\dodimensionsignal
-   \gdef\dodimensionsignal{\kern\dimensionsignal}%
+  {\def\dodimensionsignal{\kern\dimensionsignal}%
    \ifdim\lastskip=\zeropoint\relax
      \ifdim\lastkern=\zeropoint\relax
        \ifmmode
@@ -145,16 +144,70 @@
    \else
      \unskip\mathematics{\dimensionhalfspace\dimensionhalfspace\dimensiontypeface#1}%
    \fi
-   \dodimensionsignal
-   \popmacro\dodimensionsignal}
+   \dodimensionsignal}
 
 \unexpanded\def\nodimension#1%
   {\unskip#1\global\let\dodimensionsignal\relax}
 
+% %D \macros
+% %D   {super, suber}
+% %D
+% %D \TEX\ uses \type{^} and \type{_} for entering super- and
+% %D subscript mode. We want however a bit more control than
+% %D normally provided, and therefore provide \type {\super}
+% %D and \type{\suber} (\type {\sub} is already taken).
+%
+% \global\let\normalsuper=\normalsuperscript % will become obsolete
+% \global\let\normalsuber=\normalsubscript   % will become obsolete
+%
+% \newcount\supersubmode
+%
+% \newevery\everysupersub \EverySuperSub
+%
+% \appendtoks \advance\supersubmode\plusone \to \everysupersub
+%
+% \def\super#1{\normalsuperscript{\the\everysupersub#1}}
+% \def\suber#1{\normalsubscript  {\the\everysupersub#1}}
+%
+% %D \macros
+% %D   {enablesupsub}
+% %D
+% %D We can let \type {^} and \type {_} act like \type {\super}
+% %D and \type {\suber} by saying \type {\enablesupsub}.
+%
+% \bgroup
+% \catcode\circumflexasciicode\activecatcode
+% \catcode\underscoreasciicode\activecatcode
+% \gdef\enablesupsub
+%   {\catcode\circumflexasciicode\activecatcode
+%    \catcode\underscoreasciicode\activecatcode
+%    \def^{\ifmmode\expandafter\super\else\expandafter\normalsuper\fi}%
+%    \def_{\ifmmode\expandafter\suber\else\expandafter\normalsuber\fi}}
+% \egroup
+%
+% %D \macros
+% %D   {restoremathstyle}
+% %D
+% %D We can pick up the current math style by calling \type
+% %D {\restoremathstyle}.
+%
+% \def\restoremathstyle
+%   {\ifmmode
+%      \ifcase\supsubmode
+%        \textstyle
+%      \or
+%        \scriptstyle
+%      \else
+%        \scriptscriptstyle
+%      \fi
+%    \fi}
+
 %D \macros
 %D   {cramped}
 %D
-%D Cramped math:
+%D \TEX provides no primitive to force in cramped math mode. Here is
+%D a macro that does so. It is based on a solution by Don Knuth (\useurl
+%D {http://www.ctan.org/tex-archive/digests/tex-implementors/042}).
 %D
 %D \startbuffer
 %D \ruledhbox{$\left\{{x^2\over y^2}\right\}$}
@@ -192,47 +245,25 @@
 %     \ht\scratchbox-\scratchdimen
 %     \box\scratchbox}
 
-% mkii:
-%
-% \def\math_cramped#1#2%
-%   {\begingroup % added HH, made even more cramped
-%    \setbox\scratchbox\hbox
-%      {\nulldelimiterspace\zeropoint
-%       \normalstartimath\mathsurround\zeropoint#1\radical\zerocount{#2}\normalstopimath}%
-%    \ht\scratchbox-\dimexpr
-%      \ifx#1\displaystyle
-%        \fontdimen\pluseight\textfont\plusthree
-%        +.25\fontdimen\plusfive\textfont\plustwo
-%      \else
-%         1.25\fontdimen\pluseight
-%           \ifx#1\textstyle
-%             \textfont
-%           \else\ifx#1\scriptstyle
-%             \scriptfont
-%           \else
-%             \scriptscriptfont
-%           \fi \fi
-%           \plusthree
-%      \fi
-%      -\ht\scratchbox
-%    \relax
-%    \box\scratchbox
-%    \endgroup}
-
-\def\math_cramped#1#2% we have all in one family
+\def\math_cramped#1#2%
   {\begingroup % added HH, made even more cramped
    \setbox\scratchbox\hbox
      {\nulldelimiterspace\zeropoint
       \normalstartimath\mathsurround\zeropoint#1\radical\zerocount{#2}\normalstopimath}%
    \ht\scratchbox-\dimexpr
      \ifx#1\displaystyle
-            \fontdimen\pluseight\textfont\plusone
-       + .25\fontdimen\plusfive \textfont\plusone
+       \fontdimen8\textfont3
+       +.25\fontdimen5\textfont2
      \else
-        1.25\fontdimen\pluseight
-         \ifx#1\textstyle  \textfont        \else
-         \ifx#1\scriptstyle\scriptfont      \else
-                           \scriptscriptfont\fi\fi \plusone
+        1.25\fontdimen8
+          \ifx#1\textstyle
+            \textfont
+          \else\ifx#1\scriptstyle
+            \scriptfont
+          \else
+            \scriptscriptfont
+          \fi \fi
+          \plusthree
      \fi
      -\ht\scratchbox
    \relax
@@ -274,7 +305,7 @@
 
 % experiment, not yet to be used
 
-% \unexpanded\def\displaybreak
+% \def\displaybreak
 %   {\ifhmode
 %      \removeunwantedspaces
 %      \ifcase\raggedstatus\hfill\fi