Hello, The code below prompts the user for a start and end date for scraping historical temperature data from a website. I've used a few while loops to make sure the input is in the correct format and range. The problem is that once the range exception is caught and the user is prompted again, the format exception can't be caught. So the user could accidentally input a date before the earliest available date and the program would alert them of this, but then an incorrect format input would be accepted.

Is there a better way for me to handle these exceptions?

Thanks,

Dave

# First, the current date is determined
use Date::Simple::D8 (':all');
my $today = Date::Simple::D8->today();
my $end_date = $today;

# Prompt user for start date and verify it
print "Please enter the collection start date (YYYYMMDD): ";
my $start_date = <>;
chomp ($start_date);
while ($start_date !~ (/\d\d\d\d\d\d\d\d/)) {
    print "ERROR: Invalid format! Start date (YYYYMMDD): ";
    $start_date = <>;
    chomp ($start_date);
    }
while ($start_date < 18960101) {
    print "ERROR: Data prior to 18960101 is not available! Start date 
+(YYYYMMDD): ";
    $start_date = <>;
    chomp ($start_date);
    }
while ($start_date > "$today") {
    print "ERROR: Start date is in the future! Start date (YYYYMMDD): 
+";
    $start_date = <>;
    chomp ($start_date);
    }
print "Thank you, collection will begin with $start_date\n";

# Ask user if most recent available date should be used as end date
print "Would you like to collect through the most recent available dat
+e? (y/n): ";
my $ans = <>;
chomp ($ans);
if ($ans eq "n" || $ans eq "N") {
    print "Please enter the collection end date (YYYYMMDD): ";
    my $end_date = <>;
    chomp ($end_date);
    while ($end_date !~ (/\d\d\d\d\d\d\d\d/)) {
        print "ERROR: Invalid format! End date (YYYYMMDD): ";
        $end_date = <>;
        chomp ($end_date);
    }
    while ($end_date < 18960101) {
        print "ERROR: Data prior to 18960101 is not available! End dat
+e (YYYYMMDD): ";
        $end_date = <>;
        chomp ($end_date);
    }
    while ($end_date > "$today") {
        print "ERROR: End date is in the future! End date (YYYYMMDD): 
+";
        $end_date = <>;
        chomp ($end_date);
    }
    print "Thank you, collection will end with $end_date\n";
}

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In reply to Handling User Input by cheech

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