An option ‘no_#1’ asks not to load the style file ‘#1.4ht’.
<..latex ltclass..>
\ifx \@ifpackageloaded\:UnDef
\long\def\@ifpackageloaded#1#2#3{}
\fi
\def\:ifpackageloaded#1#2#3{%
\:CheckOption{no_#1}\if:Option \:Optionfalse
\else \@ifpackageloaded{#1}{#2}{#3}\fi}
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<..NO..>
\def\:ifclassloaded#1#2#3{%
\:CheckOption{no_#1}\if:Option \:Optionfalse
\else \@ifclassloaded{#1}{#2}{#3}\fi}
\def\:iffileloaded#1#2#3{%
\:CheckOption{no_#1}\if:Option \:Optionfalse
\else <.search in filelist.> \expandafter \:tempa\fi }
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<..search in filelistNO..>
\def\:temp{#1}\expandafter
\:iffil\@filelist,,<.par del.>%
\ifx \:tempa\:temp \def\:tempa{#2}\else \def\:tempa{#3}\fi
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<..latex ltclass..>+
\def\:iffil#1,#2<.par del.>{\def\:tempa{#1}\ifx \:temp\:tempa
\let\:tempb=\empty
\else
\ifx \:tempa\empty \let\:tempb=\empty
\else \def\:tempb{\:iffil#2<.par del.>}\fi
\fi \:tempb}
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We need the follwoing for definition of fonts that are introduced late, e.e.,
<..latex ltfssdcl..>
\let\document:select:group\document@select@group
\def\document@select@group#1#2#3#4{%
\ifx\math@bgroup\bgroup\else\relax\expandafter\@firstofone\fi
{%
\document:select:group{#1}{#2}{#3}{}%
\expandafter\ifx \csname n:\expandafter
\:gobble\string#1:\endcsname\relax\else
\expandafter\let\csname o:\expandafter\:gobble
\string#1:\endcsname\:UnDef
\expandafter\HLet\expandafter#1\csname
n:\expandafter\:gobble\string#1:\endcsname
\expand:after{\global\expandafter\let
\csname o:\expandafter\:gobble\string#1:\endcsname}%
\csname o:\expandafter\:gobble\string#1:\endcsname
\global\let#1=#1%
\fi
#1{#4}%
}}
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