Like I said, Composition is having an object inside another object. Where you go from there with respect to *accessing* the nested object is up to you!

package MainObject;

sub new
{
    ...
    $self->{nested} = new NestedObject;
    ...
}

sub callNestedObjectMethod
{
    my $self = shift;
    $self->{nested}->theMethod;
}
[download]

But you might not even do that. You might never export 'theMethod' in this fashion, it might only be internally used. The 'Composition' part is having NestedObject as a member of your class.

It sounds like what you want is to "take object a, b, c and make a new object that lets me call methods from all of them". That sounds like private/protected inheritance in C++, and that sounds messy. Why not explicitly write your interface as above?

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