chomp($var = <>) Hitting enter directly ends the script...

[ezechiel]

Hi, while testing the program (runs in DOS), I thought "if someone hits enter without typing a letter before, what happens?"

I tested and the script ends.. Is this normal, or how can I avoid this?

[CODE=perl]print "To which analytical division is the study belonging to?\n\n";
print "\ti: Immunology\n";
print "\tc: Chemistry\n";
print "\tq: Quit\n";
print "\n\tYour choice: ";

chomp (my $group = <>);
my @group_list = ("i","c","q" );

if (!(grep (/$group/i, @group_list))){
do{
print "\n\nYour choice is not valid.\nPlease enter a valid choice: (i/c/q)";
print "\n\tYour choice: ";
chomp ($group = <>);
} until (grep (/$group/i, @group_list));
}[/CODE]

[numberwhun]

What you want to do is to test to see if the variable, $var, has a value before moving on. Here is a quick script I wrote that does just that. And yes, it is tested to work.

#!/usr/bin/perl

use strict;
use warnings;

my $var;

do{
    print("What is your text: ");
    chomp($var = <>);
}until($var);

print("$var \n");

Hopefully that helps.

Regards,

Jeff

[ezechiel]

Hey,

thanks for the hint! It was not very nice to repeat "your choice" every time. So i had to find the solution to display "choice not valid" in case of just hitting enter. Tried some things and here is the solution:

[CODE=perl]if (!$soft || !(grep (/$soft/i, @soft_list))) {
do{
print "\n\nYour choice is not valid.\nPlease enter a valid choice (a/h/x/e/w/n/q):\n";
print "\n\tYour choice: ";
chomp ($soft = <>);
} until ($soft && (grep (/$soft/i, @soft_list)));
}[/CODE]

[numberwhun]

I am glad that it worked for you. I figured you would have to modify it in some way to fit your code, but my point was to demonstrate that you needed to test for a value.

Regards,

Jeff

[ezechiel]

:)

well, you demonstrated efficiently :)
thanks!