Clear Items Without NBT From Inventories

In most programming languages the explanation mark (!) means negative (or not), this is pretty much the same with commands. You can use the ! in the brackets after an entity type. [tag=!TAG]  This will sort out any entities with the tag "TAG". But the explanation mark is missing in the /clear command.  /clear @a stone{Tags:["TAGS"]}  will clear any item that has the tag "TAG". But you can't clear specifically items without tags. This would be a great feature because it makes dealing with items in commands more consistent. A way to implement this would be to allow for a explanation mark before the nbt data like this: /clear @a stone!{Tags:["TAGS"]}