Thank you for the quick reply. this is exactly what I was looking for.

For exiting with selection when nothing is selected, you are right. I didn't think it through well enough.
Boolean difference between a curve and a surface/solid would provide a similar result as a boolean merge. maybe MoI can smartly differentiate between that, or maybe, even better and easier, invert the operations to select the cutter first and then the target object (Blender-Style)? wouldn't that save the sea turtles from snorting all the disregarded mouses due to the extra clicks? I think this can be a bit more streamlined in one way or another, but I guess lots of complexity may arise with multiple objects and so on, so I don't know. I trust your judgment.

I will experiment with both methods and see. I feel that clicking anywhere in the 3d space to deselect and proceed would be faster and more care-free than having to precisely click the created object for selection. This would certainly be faster after arraying on a big surface (better than having to ctrl+shift+click and drag left to right from the right angle).

Thank you for that line of code.

Happy Weekend =)