Define array when making hash from arrayref - perl

Question

I am not sure if I am using the correct terminology here but I am trying to loop through an array and create a hash of arrays and values.
Currently my code looks like this:
my $endResult;
my $list = $arrayRef;
my $hash;
foreach my $hash_ref ( #$list ) {
if ( substr($hash_ref->{ID_NUMBER}, 0, 3) eq 'ABC' ) {
$hash->{'ABC'}{$hash_ref->{ID_NUMBER}}->{'VEHICLES'} = $arrayRef1;
push(#$endResult, $hash);
}
... #more ID number if statementss with different id numbers
and I get an output like this:
[
{
ABC => {
ABC1234 => {
VEHICLES => [
{ X => 11, Y => 0, Z => 12 },
{ X => 2001, Y => 100000, Z => 300 },
],
},
ABC56778 => {
VEHICLES => [
{ X => 1324, Y => 0, Z => 234 },
{ X => 666, Y => 7777, Z => 555 },
],
},
...
But what I want is for ABC to point to array of hashes (ABC1234, ABC46778) instead of how it is. Let me know if I need to clarify better but I cant figure out the right syntax to make this happen when building my hash.

Answer 1

To get your long keys into individual array refs, you need to change the assignment of your data structure. I've added a bunch of example data.
# input data
my $vehicles = [
{
'Z' => '12',
'X' => '11',
'Y' => '0',
},
{
'Z' => '300',
'X' => '2001',
'Y' => '100000',
}
];
my $list = [ { ID_NUMBER => 'ABC1234' }, { ID_NUMBER => 'ABC56778' } ];
# output data
my $endResult;
foreach my $hash_ref (#$list) {
my $hash; # needs to be inside of the loop!
if ( substr( $hash_ref->{ID_NUMBER}, 0, 3 ) eq 'ABC' ) {
push #{ $hash->{'ABC'} }, { # this becomes the array
$hash_ref->{ID_NUMBER} => { # and everything below needs
VEHICLES => $vehicles, # to be constructed directly
}
};
push #$endResult, $hash;
}
}
This will yield the following data structure (output with Data::Printer):
\ [
[0] {
ABC [
[0] {
ABC1234 {
VEHICLES [
[0] {
X 11,
Y 0,
Z 12
},
[1] {
X 2001,
Y 100000,
Z 300
}
]
}
}
]
},
[1] {
ABC [
[0] {
ABC56778 {
VEHICLES var[0]{ABC}[0]{ABC1234}{VEHICLES}
}
}
]
}
]
Please note that your choice of variable names makes this very complicated. It's hard to read and will be hell to maintain later. Always pick variable names based on what they represent. Name them something like $vehicle, $ids or $stuff_we_need_to_take_care_off_later, but not $hash1).
1: Unless you work with a hashing algorithm and we're talking about the result. :)