Re^5: Syntax for Hashes of Hashes

Personal preference, but I would write it like:

foreach my $key (@names) {
    print $myHash{$key}{'name'}, "\n";
}
[download]

Of course, that would mean that at some point you would have had to assign a hash value with the key 'name' to each nested hash.

Comment on Re^5: Syntax for Hashes of Hashes Download Code

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Re^6: Syntax for Hashes of Hashes by o2bwise (Scribe) on Jul 25, 2005 at 16:55 UTC
Hey hubb0r, Sure appreciate the assistance, but I don't think this one works. I'll supply the code. It just keeps failing for the same reason: `Use of initialized value in print at hashOfHashes.pl line 22, <INFO> line 6.` Here's the code and Line 22 is the print statement(by the way, the key values successfully print out): #!/usr/bin/perl -w use strict; my %myHash = (); my @names; open (INFO,"<info.txt"); while (<INFO>) { my ($name,$species,$gender,$age,$hairColor) = split /,/,$_; push @names,$name; $myHash{ $name } = {}; addValues( $myHash{ $name },\$name,\$species,\$gender,\$age,\$hair +Color); } print "From outside the subroutine:\n"; foreach my $key ( @names ) { print "Key:\t$key\n"; print $myHash{$key}{'name'}, "\n"; } close (INFO); sub addValues { my ( $hashNameRef,$namRef,$speRef,$genRef,$ageRef,$hairColRef ) = +@_; $hashNameRef = { name => $$namRef, species => $$speRef, gender => $$genRef, age => $$ageRef, hairColor => $$hairColRef }; print "$$hashNameRef{'name'}\t$$hashNameRef{'species'}\t$$hashName +Ref{'gender'}\t$$hashNameRef{'age'}\t$$hashNameRef{'hairColor'}\n"; } [download] And again, here is the data file: `Tony,human,male,47,gray Mark,human,male,48,brown Tyler,dog,male,11,brown Anthi,human,female,39,black Spud,cat,male,14,white Erica,human,female,23,blonde` [download] Am I doing something wrong? I don't know, man! I tried a lot of syntax variants, but no go. I always get that error message. Tony (o2bwise)	[reply] [d/l] [select]

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Re^6: Syntax for Hashes of Hashes
by o2bwise (Scribe) on Jul 25, 2005 at 16:55 UTC

Use of initialized value in print at hashOfHashes.pl line 22, <INFO> line 6.

#!/usr/bin/perl -w

use strict;

my %myHash = ();
my @names;

open (INFO,"<info.txt");

while (<INFO>)
{
    my ($name,$species,$gender,$age,$hairColor) = split /,/,$_;
    push @names,$name;
    $myHash{ $name } = {};
    addValues( $myHash{ $name },\$name,\$species,\$gender,\$age,\$hair
+Color);
}

print "From outside the subroutine:\n";
foreach my $key ( @names )
{
    print "Key:\t$key\n";
    print $myHash{$key}{'name'}, "\n";
}

close (INFO);

sub addValues
{
    my ( $hashNameRef,$namRef,$speRef,$genRef,$ageRef,$hairColRef ) = 
+@_;
    
    $hashNameRef = { 
        name        => $$namRef,
        species        => $$speRef,
        gender        => $$genRef,
        age        => $$ageRef,
        hairColor    => $$hairColRef
    };
    print "$$hashNameRef{'name'}\t$$hashNameRef{'species'}\t$$hashName
+Ref{'gender'}\t$$hashNameRef{'age'}\t$$hashNameRef{'hairColor'}\n";
}
[download]

Tony,human,male,47,gray
Mark,human,male,48,brown
Tyler,dog,male,11,brown
Anthi,human,female,39,black
Spud,cat,male,14,white
Erica,human,female,23,blonde
[download]

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