%D \module %D [ file=supp-mat, %D version=1998.09.10, %D title=\CONTEXT\ Support Macros, %D subtitle=Math, %D author=Hans Hagen, %D date=\currentdate, %D copyright={PRAGMA / Hans Hagen \& Ton Otten}] %C %C This module is part of the \CONTEXT\ macro||package and is %C therefore copyrighted by \PRAGMA. See mreadme.pdf for %C details. %D For practical reasons, I decided to move some math things to %D a support module. There is nothing spectacular here. It may move %D back to math-ini. \writestatus{loading}{Context Support Macros / Math} \unprotect %D \macros %D {mathematics, math, nomathematics, startmathmode} %D %D The \type{$} can be both an begin and end math character. %D This can lead to confusing and errorprone situations when %D macros insert \type{$}. When for instance we have defined: %D %D \starttyping %D \def\MyPlus{$\,+\,$} %D \stoptyping %D %D the sequence \type{$x^2 \MyPlus y^2 = r^2$} will expand to: %D %D \starttyping %D $x^2 $\,+\,$ y^2 = r^2$ %D \stoptyping %D %D Here the \type{\,} are given outside math mode and \TEX\ will %D definitely complain about this. A more save definition would %D have been: %D %D \starttyping %D \def\MyPlus{\mathematics{\,+\,}} %D \stoptyping %D %D Which is implemented as: \long\def\mathematics#1{\relax\ifmmode#1\else $#1$\fi} % lookahead bug reported by brooks \long\def\displaymath#1{\relax\ifmmode#1\else$$#1$$\fi} \long\def\inlinemath #1{\relax\ifmmode#1\else $#1$\fi} \let\stopmathmode\relax \def\startmathmode % cannot be used nested {\relax\ifmmode \let\stopmathmode\relax \else $\def\stopmathmode{$}% \let\stopmathmode=$ \fi} \def\startmathmode % nested variant {\relax\ifmmode \begingroup\let\stopmathmode\endgroup \else $\let\stopmathmode$% \fi} \def\nomathematics#1% {\relax\ifmmode\hbox{#1}\else#1\fi} \let\math\mathematics %D \macros %D {displaymathematics,inlinemathematics,automathematics} %D %D An example of usage of the following can be found in the MathML module: \long\def\displaymathematics#1{\relax\ifmmode#1\else\dostartformula{}#1\dostopformula\fi} \let\inlinemathematics \mathematics \def\automathematics {\relax\ifhmode\@EA\inlinemathematics\else\@EA\displaymathematics\fi} % better, esp when used in bTABLE ... eTABLE \def\automathematics {\relax \ifhmode \expandafter\inlinemathematics \else\ifintable \expandafter\expandafter\expandafter\inlinemathematics \else \expandafter\expandafter\expandafter\displaymathematics \fi\fi} %D \macros %D {dimension, nodimension} %D %D The next few macros are used for typesetting dimensions in %D such a way that spacing is acceptable. I won't spend much %D words on these macros, because they will be overloaded in %D the units module. \newsignal\dimensionsignal \def\dimensiontypeface {\tf} \def\dimensionhalfspace {\,} \unexpanded\def\dimension#1% {\def\dodimensionsignal{\kern\dimensionsignal}% \ifdim\lastskip=\zeropoint\relax \ifdim\lastkern=\zeropoint\relax \ifmmode \mathematics{\dimensionhalfspace\dimensionhalfspace\dimensiontypeface#1}% \else \mathematics{\dimensiontypeface#1}% \fi \else\ifdim\lastkern=\dimensionsignal \mathematics{\dimensionhalfspace\dimensiontypeface#1}% \else \unkern\mathematics{\dimensionhalfspace\dimensionhalfspace\dimensiontypeface#1}% \fi\fi \else \unskip\mathematics{\dimensionhalfspace\dimensionhalfspace\dimensiontypeface#1}% \fi \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=^ \global\let\normalsuber=_ \newcount\supersubmode \newevery\everysupersub \EverySuperSub \appendtoks \advance\supersubmode 1\relax \to \everysupersub % \def\dodosuper#1{\normalsuper{\the\everysupersub#1}} % \def\dodosuber#1{\normalsuber{\the\everysupersub#1}} % % \def\dosuper{\ifx\next\bgroup\expandafter\dodosuper\else\normalsuper\fi} % \def\dosuber{\ifx\next\bgroup\expandafter\dodosuber\else\normalsuber\fi} % % \def\super{\futurelet\next\dosuper} % \def\suber{\futurelet\next\dosuber} \def\super#1{\normalsuper{\the\everysupersub#1}} \def\suber#1{\normalsuber{\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`\^=\@@active \catcode`\_=\@@active \gdef\enablesupsub {\catcode`\^=\@@active \def^{\ifmmode\expandafter\super\else\expandafter\normalsuper\fi}% \catcode`\_=\@@active \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} \protect \endinput