gistfile1.txt

diffcol() {     
sed -e '
        s,^[,^[[44m^[^[[49m,g;
        s,^G,^[[44m^G^[[49m,g;
        s,^\(Index:\|diff\|---\|+++\) .*$,^[[32m&,;
        s,^@@ ,^[[33m&,;
        s,^-,^[[35m&,;
        s,^+,^[[36m&,;
        s,\r,^[[44m^M^[[49m,g;
        s,      ,    ,g;
        s,\([^[:space:]]\)\([[:space:]]\+\)$,\1^[[41m\2^[[49m,g;
        s,$,^[[0m,
' ${1:+"$@"}
}