> On Apr 11, 2017, at 6:13 AM, Mike Martin <m...@redtux.org.uk> wrote: > > Hi > > I have the following code as an example against a hash of hashes, to sort by > hashrf key > > foreach my $opt (sort {uc($options{$b}->{type}) cmp uc($options{$a}->{type})} > keys %options){ > my $type=$options{$opt}->{vtype}; > $video_type->append_text($type) if defined($type) ; > } > > The sort function works perfectly, however perl throws up the following > warning for each line > > Use of uninitialized value in uc at > > Any ideas how to get rid of the warning
Make sure that all $options{$key}->{type} values are defined: foreach my $key ( keys %options ) { $options{$key}->{type} = ‘’ unless defined $options{$key}->{type}; } Substitute something else for ‘’ depending upon where you want to sort undefined {type} values in your sort order. Jim Gibson -- To unsubscribe, e-mail: beginners-unsubscr...@perl.org For additional commands, e-mail: beginners-h...@perl.org http://learn.perl.org/