Intersect Tool Missing! Available as separate plugin.

[micheus]

I see no downside to asking user to supply operation first.

I just think that would be better if user could use the same way used for any other Wings operation.
We already use to select something, select an action and provide any other information needed.

I'm not sure about how complex this can be to manage "programmatically", but that is how I "saw" it:
user pick the initial objects;
user pick an option;
you store these selection for A "group";
you ask the user for pick new selections;
user pick other objects;
user must hit RMB to finish command;
you store these selection for B "group";
you make any consistence check before proceed;
you make the union of group A (if needed);
you make the union of group B (if needed);
then you execute the selected operation by using the latest two "grouped" objects.