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Friday, October 18, 2002 Giuseppe Bilotta wrote: GB> Hello, GB> does ConTeXt provide extensible arrows with super and subscript? GB> An extensible arrow is something like \leftarrow, \rightarrow, GB> \Leftarrow, \Rightarrow, except that it accepts super/subscripts GB> which gets typeset over or under the arrow body, which extends to GB> accomdate the length of the super and subscripts (with a minimum GB> guaranteed legth). Sorry for following up to my own post, but I found a couple of definitions in nath.sty (Nath is a wonderful LaTeX package) which might be pertinent: GB> % GB> % E x p a n d a b l e h o r i z o n t a l a r r o w s GB> % GB> GB> \def\longrightarrow@#1#2{\mathrel{\mathopen-\axis@@ GB> \axis@{#1}{#2} GB> \axis@@\mathclose\rightarrow}} GB> GB> \def\longleftarrow@#1#2{\mathrel{\mathopen\leftarrow\axis@@ GB> \axis@{#1}{#2} GB> \axis@@\mathclose-}} GB> GB> \def\longleftrightarrow@#1#2{\mathrel{\mathopen\leftarrow\axis@@ GB> \axis@{#1}{#2} GB> \axis@@\mathclose\rightarrow}} GB> GB> \pdef\to{\def\afterparse@{ GB> \longrightarrow@{\ifsp@\sp@toks@\fi}{\ifsb@\sb@toks@\fi}\next} GB> \sb@false\sp@false GB> \def\next@comm{\afterassignment\parse@next\let\next=} GB> \next@comm} GB> GB> \pdef\ot{\def\afterparse@{ GB> \longleftarrow@{\ifsp@\sp@toks@\fi}{\ifsb@\sb@toks@\fi}\next} GB> \sb@false\sp@false GB> \def\next@comm{\afterassignment\parse@next\let\next=} GB> \next@comm} GB> GB> \pdef\otto{\def\afterparse@{ GB> \longleftrightarrow@{\ifsp@\sp@toks@\fi}{\ifsb@\sb@toks@\fi}\next} GB> \sb@false\sp@false GB> \def\next@comm{\afterassignment\parse@next\let\next=} GB> \next@comm} GB> GB> \pdef\mapsto{\mathrel{\mapstochar}\mathclose{}\mathopen{}\to} GB> GB> \def\sp@toks@{\edef\@tempa{\noexpand\inline{\the\sp@toks}}\@tempa} GB> \def\sb@toks@{\edef\@tempa{\noexpand\inline{\the\sb@toks}}\@tempa} GB> GB> \def\axis@#1#2{\setbox0\scriptstylehbox@{\protectinline@true #1} GB> \er@wd=\wd0 GB> \setbox\@tempboxa\scriptstylehbox@{\protectinline@true #2} GB> \ifdim\wd\@tempboxa>\er@wd \er@wd=\wd\@tempboxa\fi GB> \@tempdima=\ht\@tempboxa GB> \advance\@tempdima\dp\@tempboxa GB> \advance\@tempdima-.42\mex GB> \vtop{\offinterlineskip GB> \hbox{\vbox{\hbox to\er@wd{\hss\box0\hss}% GB> \vskip -.26\mex GB> \hbox to\er@wd{\axis@@@\hfill}}} GB> \vskip -.26\mex GB> \hbox to\er@wd{\hss\box\@tempboxa\hss}} GB> } GB> GB> \def\axis@@{\mkern-6mu GB> \axis@@@\mskip 3mu plus \arrow@expandability mu GB> \mkern-6mu} GB> GB> \def\axis@@@{% GB> \cleaders\hbox{\o@math\mkern-3mu \icurrstyle@\mathord- \mkern-3mu\o@math}} GB> GB> \def\arrow@expandability{1.2} GB> GB> \def\longrightarrowfill{\axis@@@\hfill\mskip-6mu\rightarrow} GB> \def\longleftarrowfill{\leftarrow\mskip-6mu\axis@@@\hfill} GB> \def\longleftrightarrowfill{\leftarrow\mskip-6mu GB> \axis@@@\hfill\mskip-6mu\rightarrow} It is my understanding that this shouldn't be too hard to port to contest: \o@math is simply the "original" TeX $, the afterparse@, \ifsp@, \ifsb@ do a lookahead to see if superscripts and subscripts are used, and in case use them. Would it be hard to port this to ConTeXt? -- Giuseppe "Oblomov" Bilotta