$symbol_table{'W'} = 'wdate:';
$NEEDSAFE_HASH{'wdate:'} = 1;    # if the field contains JIS characters

sub scan_sub {
    local($href) = shift;

    if (${$href}{'date'} =~ /([A-Z][a-z][a-z]), /) {
        if ($+ eq 'Mon') {
            ${$href}{'wdate:'} = '月';
        } elsif ($+ eq 'Tue') {
            ${$href}{'wdate:'} = '火';
        } elsif ($+ eq 'Wed') {
            ${$href}{'wdate:'} = '水';
        } elsif ($+ eq 'Thu') {
            ${$href}{'wdate:'} = '木';
        } elsif ($+ eq 'Fri') {
            ${$href}{'wdate:'} = '金';
        } elsif ($+ eq 'Sat') {
            ${$href}{'wdate:'} = '土';
        } elsif ($+ eq 'Sun') {
            ${$href}{'wdate:'} = '日';
        } else {
            ${$href}{'wdate:'} = "$+";
        }
    } else {
        ${$href}{'wdate:'} = '??';
    }
}