You are assigning the result of split() to a %hash

   ## your code is effectively this:
   my %hash_list = ( " Bill 34", " Jane 28", " John 20", " Tom 19", " 
+Wall 18" );

   ## which means...
   my %hash_list = (
      # key         # value
      " Bill 34" => " Jane 28",
      " John 20" => " Tom 19",
      " Wall 18  => undef
   );
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Upon upon further inspection, if you just want to sort these in alphabetical order, you do not need to assign them to a hash... just use a simple sort, and you're done:

   print sort ( split( /,/, $names ) );
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However, if you want to sort them by, say, the number to the right of the name, then you do need to use a hash:

    my $names    = "John 20, Bill 34... etc";
    my @elems    = split( /\s*,\s*/, $names );
    my %num2name = map{ reverse split( /\s/, $_ ) } @elems;

    my @sorted   = map{ $num2name{$_} } sort { $a <=> $b } keys %num2n
+ame;
    print "@sorted\n";
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Your split is giving you the following list: ( ' John 20', ' Bill 34', ' Jane 28',' Wall 18', ' Tom 19'). Then when you sort and assign that list to a hash, it looks like:

my %hash_list = ( ' Bill 34' => ' Jane 28',
                  ' John 20' => ' Tom 19' ,
                  ' Wall 18' =>
                );
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After Compline,
Zaxo

my %hash_list = sort(split (/,/, $names));

use Data::Dumper; print Dumper(\%hash_list);  # DEBUG
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Looking at the code, it isn't instantly clear what you expect the keys and values to be. A case can be make for either of   ( "John" => 20, "Bill" => 34 ... ) or   ( "John 20" => ?, "Bill 34" => ?, ... ) To help your readers figure out your intent, it helps to give variables clear names. %hash_list is not a clear name. If you intend to map names to ages, %name_to_age is a decent choice. If you intend to count name+age strings, %name_and_age_count would reveal your intention unambiguously.

my %hash_list = map { split ' ' } split(/,/, $names);
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%hash_list = ( John => 20, Bill => 34,
               Jane => 28, Wall => 18,
               Tom => 19 );
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Thanks to all for your replies! This is what I was looking for. I must apologize for not being able to state what I needed in an understandable fashion. Please excuse me as I am still new to Perl and am just getting comfortable with the language! Thanks! PS: What would you use to sort this? Either by the key or by the value--which subroutines can be used? Thanks again.

   ## assuming
   my %hash = (
       John => 20, Bill => 34, # etc...
   );

   ## sort by name(key):
   foreach my $name ( sort keys %hash ) {
      print "$name: $hash{$name}\n";
   }

   ## sort by number(value):
   foreach my $name ( sort { $hash{$a} <=> $hash{$b} } keys %hash ) {
      print "$name: $hash{$name}\n";
   }
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