The void tag absorbs any values generated by the contents of its primary field and discards them. It does not generate any values.
The void tag is useful for wrapping around operations that would normally generate values, but the values generated are not needed or wanted. The void tag swallows any generated values so they do not spill out and pollute the console.
In the following example, a dialog box needs to be displayed to tell the user a certain action can't be performed. The dialog tag normally generates a result so the program can tell what response the user has selected. In this case the user only has one option to choose from—to close the dialog box after reading it—so we have no use for the value generated by the dialog tag and need to get rid of it somehow. The void tag is compounded with the dialog tag to allow the dialog to be displayed but destroy the value generated by the user's interaction.
<void|dialog {Function disabled. Try a different function.}>