View Generated Script

For all rule / step types, the properties panel shown in the bottom half of the screen is split into two tabs: Rule/Step, and Generated Script. Selecting the Generated Script tab shows the equivalent JavaScript that will execute when your channel is deployed and a message is sent through:

The script pane is not editable, but you can still select code and expand/collapse code folds. As shown in the screenshot above, selecting an Iterator rule/step shows you the script for the Iterator and all of its children at once.