RE: Re: Using an array in a hash

[maverick]

Just a bit of elaboration on an excellent post.

The keys and values in hashes can only be scalars, you can't directly store a array as a value. But, you can store a refrence to a array in a hash (a reference is a scalar) which is what btrott's code does.

When you want to make a reference to another variable use the \ operator.

my $ref_to_array  = \@an_array;
my $ref_to_hash   = \%a_hash;
my $ref_to_scalar = \$a_scalar;

Or if you don't want to make a variable and then make a reference, you can initialize them this way.

my $ref_to_array = [1,2,3,4];
my $ref_to_hash  = { 'key1' => 'val1', 'key2' => 'val2' };
my $ref_to_scalar = \"some string\n";

The contents can be retrieved like:

print $ref_to_array->[0];
print $ref_to_hash->{'some_key'};
print ${$ref_to_scalar};

All this stuff is explained in the o'reily (sp?) books in great detail. I'd suggest getting them. :)

/\/\averick

[tye]

The keys and values in hashes can only be scalars

And the keys can only be strings, not just any old scalar. A nit to pick, but an important one (which you probably already knew but that some readers may not have).

        - tye (but my friends call me "Tye")