The microtype package

IMPLEMENTATION: Font setup 77\MT@tr@set@space@@\MT@tr@outer@l\MT@tr@outer@r1928 }%1929 }%1930 }If the value is followed by an asterisk, the fontdimen will be scaled by the respectiveamount, otherwise the value denotes the desired dimension in the respective unit.1931 \def\MT@tr@set@space@@#1#2#3{%1932 \MT@test@ast#1*\@nil{%1933 \MT@ifdefined@c@TF\MT@tr@unit@1934 {\edef\@tempb{#1}\MT@scale@to@em}1935 {\@tempcntb=#1\relax}%1936 \@tempdima=\dimexpr \dimexpr\@tempcntb sp*\MT@dimen@six/1000\relax1937 -\fontdimen#2\MT@lsfont\relaxFor \fontdimen 2, we also have to subtract the kerning that letterspacing adds toeach side of the characters (only half if it’s for outer spacing).1938 \ifnum#2=\tw@1939 \advance\@tempdima -\dimexpr\MT@letterspace@ sp*\MT@dimen@six/#3\relax1940 \fi1941 \@tempdima=\dimexpr \fontdimen#2\MT@lsfont+\@tempdima\relax1942 }{%1943 \MT@ifempty\@tempa{\let\@tempa\MT@letterspace@}\relax1944 \@tempdima=\dimexpr \numexpr1000+\@tempa sp *\fontdimen#2\MT@lsfont/1000\relax1945 }%1946 \MT@dinfo@nl3{... : font dimen #2 (#1): \the\@tempdima}%1947 }Recall the last skip (must really be an interword space, not just a marker, nor a‘hard’ space, i.e., one that doesn’t contain stretch or shrink parts).1948 \def\MT@tr@outer@l{%1949 \ifhmode1950 \ifdim\lastskip>5sp1951 \edef\x{\the\lastskip minus 0pt}%1952 \setbox\z@\hbox{\MT@outer@space=\x}%1953 \ifdim\wd\z@>\z@1954 \MT@dinfo2{[[[ adjusting pre space: \the\MT@outer@space}%1955 \unskip \hskip\MT@outer@space\relaxDisable left outer kerning.1956 \let\MT@ls@outer@k\relax1957 \elseThe ragged2e package sets \spaceskip without glue.1958 \ifdim\lastskip=%1959 \ifnum\spacefactor