An amateur question regarding the evaluation of scalars. I have a shared routine which gets CGI params like so: 
sub get_my_params {
   my @array;
   $array[0]  = defined (param('ticket'))  ? param('ticket')    : "";
   $array[1]  = defined (param('title'))   ? param('title')     : "";
   $array[2]  = defined (param('client'))  ? param('client')    : "";
   $array[3]  = defined (param('next_step'))  ? param('next_step') : "
+";
   $array[4]  = defined (param('o_date'))  ? param('o_date')    : "";
   $array[5]  = defined (param('o_time'))  ? param('o_time')    : "";
   return @array;
}

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Then in the callin script: 
require "tickets.pm";

my ($ticket, $title, $client, $next_step, $o_date, $o_time) = get_my_p
+arams();

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During the script I want to evaluate some of the variables. They evaluate for truth correctly: 
if ($title) {}

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But if I try 
if (defined ($title)) {}

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I always get a match, even if no parameter was passed. An empty "" isn't defined, is it? When declaring empty variables, should I use undef instead of ""?

In reply to Scalar evaluation by mhearse

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