texinfo/contrib/texifont/tests/subst.tex

\input ../fattr

\ftracelevel=3

\newfontattr family     Fam1
\newfontattr family     Fam2
\newfontattr family     Fam3
\newfontattr encoding   Enc1
\newfontattr encoding   Enc2
\newfontattr encoding   Enc3
\newfontattr encoding   Enc4
\newfontattr slant      Slant1
\newfontattr slant      Slant2
\newfontattr slant      Slant3
\newfontattr slant      Slant4

\fontsubstpre   = Fam1
                - slant
                + Enc1

\bye