In this version of the tutorial ( http://www.tersus.com/#Id=2647 ) we read
"For example, look at the display hierarchy of the popup we are modeling, which contains a label, a text area, a footer and 2 buttons (see screenshot of the Display - below left). This is represented by a data structure of the popup, which contains data structures for the text area, button and label; the text area contains another data structure for its value (see screenshot of the Display Data Element - below right)."
But the screenshots are stacked. The other rendering of the tutorial:
does show them side by side.
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