Old amstex.sty: 1985, 1986 BY MICHAEL SPIVAK
<..vanilla.4ht..>
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% vanilla.4ht 2014-07-12-22:36 %
% Copyright (C) 1997--2009 Eitan M. Gurari %
<.TeX4ht copyright.>
<.vanilla.sty.>
<.config amsppt + vanilla shared.>
<.config vanilla.sty utilities.>
<.config vanilla.sty shared.>
\Hinput{vanilla}
\endinput
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<..vanilla.sty..>
\expandafter\def\csname title\endcsname{\title@true
\bgroup \let\halign=\TeXhalign \HRestore\noalign \let\\=\cr\a:title
\halign\bgroup\tenbf\hfill\ignorespaces##\unskip\hfill\cr}
\def\endtitle{\cr\egroup\b:title\egroup}
\expandafter\def\csname author\endcsname{\bgroup
\let\halign=\TeXhalign \HRestore\noalign \let\\=\cr\a:author
\halign to \hsize\bgroup\smc\hfill\ignorespaces##\unskip\hfill\cr}
\def\endauthor{\cr\egroup\b:author\egroup}
\expandafter\let\csname heading\endcsname=\empty
\expandafter\let\csname endheading\endcsname=\empty
\NewSection\heading{}
\let\x:heading=\heading
\def\heading#1\endheading{{\let\cr=\space \let\\=\space
\x:heading{#1}}}
\expandafter\let\csname subheading\endcsname=\empty
\NewSection\subheading{}
\expandafter\def\csname proclaim\endcsname#1{\medbreak\a:proclaim
\noindent\smc\ignorespaces #1\unskip.\b:proclaim
\enspace\sl\ignorespaces}
\expandafter\def\csname endproclaim\endcsname{\c:proclaim\medskip\rm}
\expandafter\def\csname demo\endcsname#1{\par \a:demo
\noindent{\smc\ignorespaces#1\unskip\enspace}\b:demo
\rm \ignorespaces}
\expandafter\def\csname enddemo\endcsname{\c:demo\par}
\NewConfigure{demo}{3}
\def\footnote{\let\@sf=\empty\ifhmode\edef\@sf{\spacefactor
=\the\spacefactor}\/\fi \futurelet\next\footnote@}
\def\footnote@{\ifx"\next\let\next\footnote@@\else
\let\next\footnote@@@\fi\next}
\def\footnote@@"#1"#2{%
\gHAdvance\FNnum 1 \def\:temp{#1}\ifx \:temp\empty
\def\:temp##1[##2]##3{##1[##2]{*}}\expandafter\:temp \fi
\HPageButton[fn\FNnum]{#1}\BeginHPage[fn\FNnum]{ }{#2}\EndHPage{}}
\HAssign\FNnum = 0
\def\footnote@@@#1{%
\HPageButton[nf\the\footmarkcount@]{$^{\number\footmarkcount@}$}%
\BeginHPage[nf\the\footmarkcount@]{ }
{{\HCode{<sup>}{\number\footmarkcount@}\HCode{</sup>}}{#1}\global
\advance\footmarkcount@ by 1}\EndHPage{}}
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<..vanilla.sty..>+
\def\brute:halign{\let\:HAlign=\halign \let\:NOalign=\noalign
\let\halign=\TeXhalign \HRestore\noalign
\let\sv:Row=\HRow \let\sv:Col=\HCol \def\HRow{0}}
\def\endbrute:halign#1{%
\csname d:#1\endcsname\csname b:#1\endcsname
\global\let\HRow=\sv:Row \global\let\HCol=\sv:Col}
\def\abt:hlgn#1{\csname\ifnum \HRow=0 a\else d\fi :#1\endcsname
\g:Advance\HRow by 1 \gdef\HCol{1}%
\csname c:#1\endcsname\csname e:#1\endcsname\let\halign=\:HAlign
\let\noalign=\:NOalign}
\def\bbt:hlgn#1{\g:Advance \HCol by 1 \csname
e:#1\endcsname\let\halign=\:HAlign
\let\noalign=\:NOalign}
\def\:temp{\vcenter\bgroup \brute:halign
\vspace@\Let@\openup\jot\m@th\ialign
\bgroup \strut\hfil\abt:hlgn{aligned}%
$\displaystyle{##}$\f:aligned
&\bbt:hlgn{aligned}$\displaystyle{{}##}$\f:aligned\hfil\crcr}
\HLet\aligned=\:temp
\def\:temp{\crcr\egroup
\endbrute:halign{aligned}\egroup}
\HLet\endaligned=\:temp
\NewConfigure{aligned}{6}
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<..vanilla.sty..>+
\def\:temp{\vcenter\bgroup\Let@\vspace@ \brute:halign
\normalbaselines
\m@th\ialign\bgroup\hfil\abt:hlgn{matrix}$##$\f:matrix\hfil&&\quad\hfil
\bbt:hlgn{matrix}$##$\f:matrix\crcr
\mathstrut\crcr\noalign{\kern-\baselineskip}}
\HLet\matrix=\:temp
\def\:temp{\crcr\mathstrut\crcr\egroup
\endbrute:halign{matrix}\egroup}
\HLet\endmatrix=\:temp
\NewConfigure{matrix}{6}
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<..vanilla.sty..>+
\def\:temp{\left\{\,\vcenter\bgroup\vspace@ \brute:halign
\normalbaselines\openup\jot\m@th
\Let@\ialign\bgroup\abt:hlgn{cases}$##$\f:cases
\hfil&\quad\bbt:hlgn{cases}$##$\f:cases\hfil\crcr}
\HLet\cases=\:temp
\def\:temp{\crcr\mathstrut\crcr\egroup
\endbrute:halign{cases}\egroup\right.}
\HLet\endcases=\:temp
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<..vanilla.sty..>+
\def\ralign@#1\endalign{\displ@y\Let@\tabskip\centering
\append:def\f:align{\ifx \dn:hlgn\:UnDef \else
\global\let\dn:hlgn=\:UnDef \endbrute:halign{align}\fi}%
\brute:halign \halign{\abt:hlgn{align}$\displaystyle
{##}$\f:align&\bbt:hlgn{align}$\displaystyle{{}##}$\f:align
&\bbt:hlgn{align}\hbox{(\rm##\unskip)}\f:align\crcr
#1\global\let\dn:hlgn=\empty\crcr}}
\def\lalign@
#1\endalign{\displ@y\Let@\tabskip\centering
\append:def\f:align{\ifx \dn:hlgn\:UnDef \else
\global\let\dn:hlgn=\:UnDef \endbrute:halign{align}\fi}%
\brute:halign \halign{\abt:hlgn{align}$\displaystyle
{##}$\f:align&\bbt:hlgn{align}$\displaystyle{{}##}$\f:align
&\bbt:hlgn{align}\hbox{(\rm##\unskip)}\f:align\crcr
#1\global\let\dn:hlgn=\empty\crcr}}
\NewConfigure{align}{6}
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