Question

I’m trying to make the script exit when a blank query is entered. From what I’ve read, this code should work fine, but doesn’t seem to want to, because “” isn’t numeric. What is the workaround?

if(($#ARGV < 0) || ($ARGV[0] == "")){
  print "$0: Enter a query.\n";
  exit 1;
}

To clarify,

perl run.pl "query"

should work, while

perl run.pl ""

should prompt for a string.

Answer 1

Try

if(($#ARGV < 0) || ($ARGV[0] eq "")){
  print "$0: Enter a query.\n";
  exit 1;
}

eq for string comparison.