It seems like you want something along these lines, where you suck all the args of the sub into a hashref, so that you can use exists to see if a param was passed in or not. 
sub update_info {
  my $obj = shift;
  my $params = { @_ };
  my $value = exists $params->{value} ? $params->{value} : undef;
  ...
}

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In reply to Re: Hashes and keys... by davidrw
in thread Hashes and keys... by mkenney

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