Hey all, i'm writing a pretty specific reporting tool for some data crunching i'm working on, and stumbled across a little issue that i'd missed before. Anyway, lets say I have a class that's implemented with a hashref, that includes the data member "Big_List", i.e. 
    $self->{'Big_List'} = [many elements];

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Then, in another method, i need to operate on each element of the big list. I could write a method called GetBigList, and methods that want to operate on the list could access each element by looping through the return results of GetBigList() 
sub GetBigList {
    my $self = shift;
    return $self->{'BigList'};
}

sub SomeOperation {
    my $self = shift;

    foreach my $element ( @{$self->GetBigList()} ) {
        # do stuff to element, etc.
    }
}

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... and encapsulation is happy.

But, there is a lot of overhead because GetBigList() returns a copy of the list to SomeOperation(). So, i could rewrite SomeOperation() to look like: 
sub SomeOperation {
    my $self = shift;

    foreach my $element ( @{ $self->{'Big_List'} } ) {
        # do stuff to element, etc.
    }
}

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And i have broken encapsulation, but my scripts should incur much less overhead.

I'm really on the fence on this one, i'm generally VERY strict about not breaking encapsulation, but this situation may call for it. Of course, breaking encapsulation usually comes back and bites one on the posterier as updates occur.

Any thoughts?

In reply to Array copy or encapsulation break? by shemp

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