From type/BagHash

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method remove(BagHash: \to-remove, *%_ --> Nil)

When to-remove is a single item, remove reduces the weight of that item by one. If this results in the item having a weight of 0, this removes the item from the BagHash. If the item is not present in the BagHash, remove has no effect. When to-remove is a List, Array, Seq, or any other type that does the Iterator Role, remove reduces the weight of each element by 1 and removes any items with the resulting weight of 0.

Note: Added in version 2020.02.