We describe a method for computing closed sets with data-dependent constraints. Especially, we show how the method can be adapted to find frequent closed sets in a given data set. The current preliminary implementation of the method is quite inefficient but more powerful pruning techniques could be used. Also, the method can be easily applied to wide variety of constraints. Regardless of the potential practical usefulness of the method, we hope that the sketched approach can shed some additional light to frequent closed set mining.