Version 1 - works fine 
package SomeMod;
sub new {
    my $obj = bless{
        Order=>[],
        Items=>{}, 
        Config=>{},
    }, shift; 
    while ( @_ ) {
        my ( $key, $val ) = ( shift, shift ) ;        
        push @{$obj->{Order}}, $key; 
        $obj->{Items}{$key} = $val;
    }
    return $obj
}
1;

### main 
use SomeMod;
my %Items_Key_Value_pairs = (A => "Apple", B => "Banana", C => "Cat");
my $obj = SomeMod -> new ( %Items_Key_Value_pairs ) ;

[download]

Version 2 - I want to change the constructor interface 
package SomeMod;
sub new {
    my $obj = bless{
        Order=>[],
        Items=>{}, 
        Config=>{},
    }, shift; 
    
    my %arg = @_ ; 
    
    while ( @{$arg{Items}} ) { # BLOW! 'Not an ARRAY reference'
        my ( $key, $val ) = ( shift, shift ) ;        
        push @{$obj->{Order}}, $key; 
        $obj->{Items}{$key} = $val;
    }
    
    # ... deal with config ...
    
    return $obj
}
1;

### main 
use SomeMod;
my %Items_Key_Value_pairs = (A => "Apple", B => "Banana", C => "Cat");
my %some_config_param = ();

my $obj = SomeMod -> new ( 
    Items => { %Items_Key_Value_pairs } ,
    Config => { %some_config_param }
) ;

[download]

I know that's not an ARRAY ref, but since I want to learn the appear order, can I do anything to access this HASH ref like other ordinary array ( they still a list right) ?

Or, when I do Items => {... }, this list already "digested" in a hash form thus not feasible to access like an array anymore?

Though I already have a work around by using Items => [ A => "Apple", B => "Banana" ... ], I still interest to know if I can force to access a Hash ref like Array, same as I did in Version 1

Thank you very much

In reply to Force access a Hash ref as Array ref by exilepanda

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