Multiple Hash Keys Module

[arunhorne]

Monks

I want to create hash that maps a single key to multiple values. My current way of doing this is to use and array reference:

my %hash = ("key"=>["value1","value2"]);

However, I was wondering if anyone knows of a module that provides this sort of behaviour whilst abstracting the specifics of creating array refs etc?

____________
Arun

[Zaxo]

With mild quibbles on quoting, what you have is fine. It's simple and if it does what you want it would be hard to improve on. If anything, it's a little more abstracted than some might like. I can't think of any modular sugar that I would prefer to your code.

As for quoting, the '=>' form of comma stringifies its left hand side, so key can remain unquoted. If the value strings contain no variables to interpolate, single quotes are preferred, and if thay have no whitespace, qw() might be handy.

After Compline,
Zaxo

[artist]

Zaxo has pointed you in the right direction, but if for any means, if you need 'modular sugar',you can use something like this with better design.

package Hash;
sub new {
    my $class = shift;
    my $self = {};
    bless $self,$class;
}

sub addKey {
    my $self = shift;
    my $key = shift;
    $self->{$key};
}
sub printKeys {
    my $self = shift;
    foreach (keys %{$self}){
    print "$_\n";
       
    }
}
sub addValues {
    my $self = shift;
    my $key = shift;
    push @{$self->{$key}}, @_;
}
sub printValues {
    my $self = shift;
    my $key = shift;
    print "$key\t";
    foreach (@{$self->{$key}}){
        print "$_\t";
    }
    print "\n";
}
package main;

my $hash = new Hash;
$hash->addKey('fruit');
$hash->addValues('fruit', 'apple');
$hash->addValues('fruit','orange');
$hash->printValues('fruit');
$hash->addKey('operating system');
$hash->addValues('operating system', 'Linux','Windows XP');
$hash->printValues('operating system');

artist

[arthas]

The Perl solution is, IMHO, very immediate and, also, very well documented in the pod pages. You probably need nothing more abstract.

Michele.

[gmpassos]

Keep It Simple! Using the Array ref is better.

But maybe this can help you: Object::MultiType

Graciliano M. P.
"The creativity is the expression of the liberty".

[arunhorne]

Further to this thread I have written an object to satisfy the task set out for this node, more details here

____________
Arun