$ perl -ce '$no_days = "(TO_DAYS(dateadded)-TO_DAYS(Now())>=-$newdateadded)";'
-e syntax OK

##</code><code>##

$ perl -MO=Deparse,-p -e '$no_days = "(TO_DAYS(dateadded)-TO_DAYS(Now())>=-$newdateadded)";'
($no_days = "(TO_DAYS(dateadded)-TO_DAYS(Now())>=-$newdateadded)");
-e syntax OK

##</code><code>##

$ perl -e '
    $newdateadded = "NDA";
    $no_days = "(TO_DAYS(dateadded)-TO_DAYS(Now())>=-$newdateadded)";
    print $no_days;
'
(TO_DAYS(dateadded)-TO_DAYS(Now())>=-NDA)