"
#!perl -i.bak
@ARGV = ($0);
while (<>) {
    $end = 1 if /^__END__/;
    print if $end < 2;
    $end++ if /^"/ and $end;
    if (eof) {
        open my $f, "</usr/share/X11/locale/$ENV{LANG}/Compose" or die "<$!";
        print for <$f>; # manipulate the line here
        close $f;
    }
}
__END__
"
# normal lines start here
# etc. etc.