Set Operations for Lists of DisplayBoxes?

[#1]

How to apply set operations to lists of display boxes?

- remove duplicates

- intersect

- subtract

Plan B:
Is there a function which returns the unique position of a display box in the display tree?

With the information about the position (pos 1.2.4.1.2 vs. 1.2) one could pre-execute the set operations for positions and the apply it to the lists with display boxes.

I found

Get Display Path( )

which gives the Xpath or subscript function to get from one Level to another level. But I didn't find a function Get Pos ...

Names Default to Here(1);
dt = Open( "$SAMPLE_DATA/Big Class.jmp" );
gb = dt << Graph Builder(
	Variables( X( :height ), Y( :weight ), Overlay( :sex ) )
);
gb2 = gb << Clone box();

nw = New Window("test",H List Box (gb2,gb2));


(nw << xpath("//AxisBox")) << parent;

[#2]

If you have a list of references and a reference you wish to find you can use Contains

Names Default To Here(1);

nw = new window("",
	vlb = v list box()
);

tb1 = Text Box("a");
tb2 = Text Box("b");
tb3 = Text Box("c");

vlb << Append(tb1);
vlb << Append(tb3);
vlb << Append(tb2);

Contains(vlb << XPath("//TextBox"), tb2); //3

[#3 · Accepted solution]

ah, right, so all the functions work
- even the associative array.

very useful, thanks

Hm, strange - seems that when I tried it first I did something wrong ...

Names Default To Here(1);

nw = new window("",
	vlb = v list box(vlb2 = v list box());
	
);

tb1 = Text Box("a");
tb2 = Text Box("b");
tb3 = Text Box("c");

vlb << Append(tb1);
vlb << Append(tb2);
vlb2 << Append(tb3);

aa1 = associative array((vlb << XPath("//TextBox"))<< parent);
aa2 = associative array((vlb2 << XPath("//TextBox"))<< parent);

aa1 << intersect(aa2);
show(aa1)