I know I can validate that the input argument was there via the following bit of code: 

chomp(my $in1 = $ARGV[0] || '');
if (defined $in1) {
    #Validate;
}

[download]

Have you ever encountered a case where $in1 was not defined?

Maybe you want to directly check the number of arguments in @ARGV or look at what the || operator does?

Maybe the following code helps you analyze what happens better:

my $in1 = $ARGV[0] || 'user-did-not-pass-an-argument');
print $in1;

[download]

Run the above code with

perl -w myscript.pl # no argument
perl -w myscript.pl "" # empty argument
perl -w myscript.pl 0 # zero argument
perl -w myscript.pl something-else # other argument

[download]

In reply to Re: Using number "0" as an input argument by Corion
in thread Using number "0" as an input argument by Doozer

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