Yes, an empty string is defined; if you want to see whether a defined string is empty or not, use ($title ne '').

If it's OK for these values to be undef (if you'll be checking defined($title) before printing them or whatever), you may want to consider:

sub get_my_params {
  return(param('ticket'),
         param('title'),
         param('client'),
         param('next_step'),
         param('o_date'),
         param('o_time')
  );
}
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But what you have is good, if you never want them to be undef.

for $a(-2,12){for $b(0..7){$c=0;$_?hex substr(
ef7fa1866706caeff02289402844,2*$_+$a,2)&2**(7-$b):0
and $c+=2**(7-$_)for(0..7);print chr $c;}}
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