However the loop never enters again in case of a wrong input.

Well, a while loop stops when the condition isn't true anymore. That's a feature ;-)

If you don't want that behaviour, don't use a while loop with the regex match in the condition, rather something like this:

while (<>) {
    chomp;
   if (m/your regex here/) {
        # work with it
   } else {
       print "Input '$_' not recognized as a date\n";
  }
}
[download]

Update: I think you shouldn't try to match only numbers in the allowed range, because it makes the regex overly complicated, and you won't catch all errors in the regex anyway (think of February 30th), so you have to validate your input after the regex in any case.

Something as simple as m/^\d\d-\d\d-\d\d$/ might do for you.

Because of your missing code tags, I can't really tell, but it seems your loop runs WHILE the re matches and not UNTIL it matches.

and you don't anchor (/^…$/) your RE so "this 123401-01-0123456 is not a date" as input will also match.

Hi,

I would recommend you to take a look at modules like Date::Manip.

Regards,

1st : Tell us what you want from this script: 

I suppose it's : make someone enter a date until what he/she
types is a "good" date (in "good" format). right ? 

If yes, you loop until the entry is OK ?

2nd : the format you show is not clear  : 
      It could be : 2008, January the 1st 
                    2001, January the 8th, ... and so on
It should be better to write it MM-DD-YY (for month, day, year).  (FYI
+ :I'm french and we display dates as DD/MM/YY)

for this format, the regex "could" be:
(0[1-9]|1[0-2])-(0[1-9]|[12][0-9]|3[01])-\d\d 
but : it ignores that the maximum number of days depends on the month(
+28,29,30,31), it ignores leap years (February 28th  or 29 th ?)

You should use the function "timelocal()" from the standard module
 "Time::Local" : try to transform the date you have to validate into a
+n "epoch" time (as the function time() returns) : if the function fai
+ls, the date is wrong : 
this script seems to work:

use Time::Local timelocal;
my ($m,$d,$y);
do
{
    my $date;
    print "date (MM-DD-YY) ? ";
    $date=<>;
    chomp($date);
    ($m,$d,$y)=split(/-/,$date); 
    $m -= 1;
    $y += 1900;
}
until(timelocal(0,0,0,$d,$m,$y));
[download]

Apologizes : The previous script hanged on bad date, this one runs better (thanks to "eval") !

use Time::Local timelocal;
my ($m,$d,$y,$t);
do
{
    my ($date);
    print "date (MM-DD-YY) ? ";
    $date=<>;
    chomp($date);
    ($m,$d,$y)=split(/-/,$date); 
    $m -= 1;
    $y += 1900;
    $t = eval "timelocal(0,0,0,$d,$m,$y)";
}
until (!$t);
[download]