delim_0 "
pfill " delim_1 "
pfill " delim_2 "
pfill "

item_x1 "
efill
subitem " item_x2 "
efill
subsubitem "

lethead_prefix "
bf
hfil " lethead_suffix "
hfil
nopagebreak" lethead_flag 1

preamble "
begintheindex
makeatletter
scan@allowedfalse"

postamble "
endtheindex"