Time::Piece (in core since 5.10) has strptime, which would throw an error on an invalid date, and if you do something like:
# no 29 feb 2001
my $dt = Time::Piece->strptime("2001-02-29", "%F");
# will return 2001-03-01 
print $dt->strftime("%F");

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Time::Piece will correct your date, and if you need to catch this happening, compare the output of strftime on that object to the original date string. Any invalid date will throw an error that you can catch with eval or one of the many exception catching modules.
my $dt = eval { 
          Time::Piece->strptime("2001-04-32", "%F")
         } or warn "This is not a valid date ($@).\n";

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In reply to Re: How to check if a date exists ? by james2vegas
in thread How to check if a date exists ? by HJO

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