LaTeX: (u)pLaTeX で everysel できるかもしれないやつ

pxeverysel.sty

% pxeverysel.sty

%% package declaration
\NeedsTeXFormat{LaTeX2e}
\ProvidesPackage{pxeverysel}

%% preparations
\def\pxys@pkgname{pxeverysel}
\def\pxys@warn{\PackageWarningNoLine\pxys@pkgname}

%% load it
\RequirePackage{everysel}

%--------------------------------------- helpers

%% unique tokens
\def\pxys@mark{\pxys@mark@}
\def\pxys@fin{\pxys@fin@}

%% \pxys@patch@cmd\CMD{<pre>}{<post>}{<new>}
\@onlypreamble\pxys@patch@cmd
\def\pxys@patch@cmd#1#2#3#4{%
  \def\pxys@next##1#2##2#3##3\pxys@mark##4\pxys@fin{%
    \ifx\pxys@mark##4\pxys@mark
      \let\pxys@fragment\relax
    \else
      \def\pxys@fragment{##2}%
      \def#1{##1#4##3}%
    \fi}%
  \expandafter\pxys@next#1\pxys@mark#2#3\pxys@mark\pxys@fin}

%% \pxys@append@to\CSa\CSb
\@onlypreamble\pxys@append@to
\def\pxys@append@to#1#2{%
  \expandafter\g@addto@macro\expandafter#1\expandafter{#2}}

%% \pxys@term
\let\pxys@term\relax

%---------------------------------------

%% variables
\let\pxys@self@hook\@empty
\let\pxys@everysel@hook\@empty
\@onlypreamble\pxys@selectfont
\let\pxys@selectfont\relax
\@onlypreamble\pxys@org@selectfont
\let\pxys@org@selectfont\relax
\@onlypreamble\pxys@new@selectfont
\let\pxys@new@selectfont\relax

%% \@EverySelectfont@Init redefined
\@onlypreamble\pxys@EverySelectfont@Init
\let\pxys@EverySelectfont@Init\@EverySelectfont@Init
\def\@EverySelectfont@Init{%
  \pxys@preproc
  \pxys@EverySelectfont@Init
  \pxys@postproc}

%% \pxys@preproc
\@onlypreamble\pxys@preproc
\def\pxys@preproc{%
  % prepare
  \expandafter\let\expandafter\pxys@selectfont
      \csname selectfont \endcsname
  \let\pxys@org@selectfont\pxys@selectfont
  % extract "pre-\size@update" insertion
  \pxys@append@to\pxys@selectfont\pxys@term
  \pxys@patch@cmd\pxys@selectfont
    {\font@name\enc@update}{\size@update\pxys@term}%
    {\font@name\pxys@self@hook\pxys@everysel@hook
     \size@update\enc@update}%
  \ifx\pxys@fragment\relax
    \let\pxys@selectfont\pxys@org@selectfont
    % extract "pre-\enc@update" insertion
    \pxys@patch@cmd\pxys@selectfont
      {\pickup@font\font@name}{\size@update\enc@update}%
      {\pickup@font\font@name\pxys@self@hook\pxys@everysel@hook
       \size@update\enc@update}%
    \ifx\pxys@fragment\relax % failure
      \let\pxys@selectfont\relax
    \else
      \pxys@append@to\pxys@self@hook\pxys@fragment
    \fi
  \else
    \pxys@append@to\pxys@self@hook\pxys@fragment
  \fi
  \let\pxys@new@selectfont\pxys@selectfont
  % prepare for everysel routine
  \let\CheckCommand\@gobble}

%% \pxys@postproc
\@onlypreamble\pxys@postproc
\def\pxys@postproc{%
  \let\CheckCommand\pxys@CheckCommand
  \let\pxys@CheckCommand\@undefined
  \expandafter\let\expandafter\pxys@selectfont
      \csname selectfont \endcsname
  % extract the code insertion by everysel
  \pxys@patch@cmd\pxys@selectfont
    {\pickup@font\font@name}{\size@update\enc@update}{}%
  \ifx\pxys@fragment\relax % failure
    \let\pxys@new@selectfont\relax
  \else % success
    \pxys@append@to\pxys@everysel@hook\pxys@fragment
  \fi
  % commit hte change
  \ifx\pxys@new@selectfont\relax % failure
    \let\pxys@selectfont\pxys@org@selectfont % revert
    \pxys@warn{Failed in patching \string\selectfont}%
  \else % success
    \let\pxys@selectfont\pxys@new@selectfont
  \fi
  \expandafter\let\csname selectfont \endcsname\pxys@selectfont}

%--------------------------------------- done
\endinput
%% EOF

test-pxeverysel.tex

% upLaTeX 文書
\documentclass[uplatex,a4paper]{jsarticle}
\usepackage{pxeverysel}
\makeatletter %!!!!!!!!!!!!!!! TeX code BEGIN
\EverySelectfont{% tractfnt みたいなの
  \typeout{Switching to \font@name!}}
\makeatother  %!!!!!!!!!!!!!!! TeX code END
\begin{document}

{\TeX}はアレ{\sffamily{\TeX}はアレ{\Large{\TeX}はアレ}}

\end{document}

everysel の代わりに、あるいは、everysel に追加して、コレを読み込む。