How to create objects out of each element in array? - arrays

Question

I have a module with a new constructor:
package myClass;
sub new
{
my $class = shift;
my $arrayreference = shift;
bless $arrayreference, $class;
return $arrayreference;
};
I want to do something like:
foreach $ref (#arrayref)
{
$array1 = myClass->new($ref);
}
$array1 is being rewritten each time, but I want each element in the array to have a distinct object name (ex. $array1, $array2, $array3 etc.)

Answer 1

If you are working with a plural data structure (an array), then you need to store the result into a plural container (or multiple scalar containers). The idomatic way to do this is to use the map function:
my #object_array = map {myClass->new($_)} #source_array;
If you know that #source_array contains a fixed number of items, and you want scalars for each object:
my ($foo, $bar, $baz) = map {myClass->new($_)} #source_with_3_items;

Answer 2

I think you should use some hash or array to contain the objects.
foreach $ref (#arrayref)
{
push #array, myClass->new($ref);
$hash{$key++} = myClass->new($ref);
}
thus you can access them with $array[42] or $hash{42}.

Answer 3

There is essentially no name difference between $array[1] and $array1. There is a programmatic difference in that $array[1] can be "pieced together" and, under modern Perl environments $array1 can't. Thus I can write $array[$x] for any valid $x and get an item with a "virtual name" of $array.$x.
my #objects = map { MyClass->new( $_ ); } #data_array;
Thus, if you just want to append a number, you probably just want to collect your objects in an array. However, if you want a more complex naming scheme, one or more levels of hashes is probably a good way to go.
If you had a way to derive the name from the object data once formed, and had a method called name, you could do this:
my %object_map
= map { my $o = MyClass->new( $_ ); ( $o->name => $o ); } #data_array
;

Answer 4

Are you are trying to do it in place?
my #objects = (
{ ...args for 1st object... },
{ ...args for 2nd object... },
...
);
$_ = Class->new($_) for #objects;
However, you should avoid reusing variables like that.
my #object_data = (
{ ...args for 1st object... },
{ ...args for 2nd object... },
...
);
my #objects = map Class->new($_), #object_data;

Answer 5

I agree with Ade YU and Eric Strom, and have +1'd their answers: you should use one of their approaches. But what you ask is technically possible, using symbolic references, so for completeness' sake:
foreach my $i (0 .. $#arrayref)
{
no strict refs;
my $varname = 'array' . ($i + 1);
${$varname} = myClass->new($arrayref[$i]);
}