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diff --git a/tex/context/base/filt-ini.mkii b/tex/context/base/filt-ini.mkii
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+%D \module
+%D   [       file=filt-ini,
+%D        version=2000.09.19,
+%D          title=\CONTEXT\ Filter Macros,
+%D       subtitle=Initialization,
+%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.
+
+\writestatus{loading}{ConTeXt Filter Macros / Initialization}
+
+% \ifx\OmegaVersion\undefined
+
+%            \let\definefiltersynonym  \gobbledoubleempty
+%            \let\definefiltersequence \gobbledoubleempty
+% \unexpanded\def\usefiltersequence   {\gobblesingleempty}
+%            \let\usefilter            \gobblesingleempty
+%            \let\truefiltername       \gobbleoneargument
+
+%   \expandafter \endinput
+% \fi
+
+\unprotect
+
+%D The real work starts here.
+
+% We need the {\??ot::#1} check because otherwise aleph will crash. Taco's
+% torture test:
+%
+% \ocp\ArabicContext = contextual
+%
+% \dorecurse {5000} {
+%     \message{[\recurselevel]}
+%     \ocplist\Arabic=\addbeforeocplist 1 \ArabicContext \nullocplist
+% }
+
+%D \macros
+%D   {definefiltersynonym}
+
+\def\definefiltersynonym
+  {\dodoubleargument\dodefinefiltersynonym}
+
+\def\dodefinefiltersynonym[#1][#2]%
+  {\setvalue{\??or#1}{#2}}
+
+%D \macros
+%D   {truefiltername}
+
+\def\truefiltername#1%
+  {\ifundefined{\??or#1}#1\else\truefiltername{\getvalue{\??or#1}}\fi}
+
+%D \macros
+%D   {definefiltersequence}
+
+\def\definefiltersequence
+  {\dodoubleargument\dodefinefiltersequence}
+
+% \def\dodefinefiltersequence[#1][#2]%
+%   {\setvalue{\??ot#1}{#2}}
+
+\def\dodefinefiltersequence[#1][#2]%
+  {\setxvalue{\??ot#1}{#2}%
+   \letgvalue{\??ot::#1}\v!stop}
+
+%D \macros
+%D   {usefiltersequence}
+%D
+
+\def\magicocpnumber{1}
+
+% one can do:
+%
+%  \definefiltersequence
+%    [farsi]
+%    [utf8 to unicode16=>5,
+%     persian fix,
+%     arabic analysis=>3,
+%     arabic glyphs]
+%
+% so, => is used to signal a priority
+
+\def\dodousefiltersequence#1%
+  {\expandafter\ocp\csname\??or:#1\endcsname=\truefiltername{#1}\relax
+   \splitstring#1\at=>\to\!!stringa\and\!!stringb
+   \edef\!!stringb{\number\ifx\!!stringb\empty\magicocpnumber\else\!!stringb\fi}%
+   \appendetoks
+     \noexpand\addbeforeocplist
+     \!!stringb\space
+     \expandafter\noexpand\csname\??or:\!!stringa\endcsname
+   \to \scratchtoks}
+
+\unexpanded\def\usefiltersequence[#1]%
+  {\doifdefined{\??ot::#1}%
+     {\doifvalue{\??ot::#1}\v!stop
+         {\scratchtoks\emptytoks
+          \expanded{\processcommalist[\getvalue{\??ot#1}]}\dodousefiltersequence
+          \expanded{\global\ocplist\csname\??ot:#1\endcsname=\the\scratchtoks}\nullocplist
+          \letgvalue{\??ot::#1}\v!start}%
+       \expanded{\pushocplist\csname\??ot:#1\endcsname}\relax}}
+
+%D \macros
+%D   {usefilter}
+
+\def\dousefilter#1%
+  {\doifundefined{\c!file\f!filterprefix#1}%
+     {\letvalue{\c!file\f!filterprefix#1}\empty
+      \makeshortfilename[\truefilename{\f!filterprefix#1}]%
+      \startreadingfile
+        \readsysfile{\shortfilename.mkii}
+          {\showmessage\m!filters1{#1}}
+          {\showmessage\m!filters2{#1}}%
+      \stopreadingfile}}
+
+\def\usefilter[#1]%
+  {\processcommalist[#1]\dousefilter}
+
+\protect \endinput