I was wondering, if I have some constraints I want to apply with such-that

should they be as early as possible in the generator definition or as late as possible?

I would guess better to cut early to avoid extra computation

creating some generators for this pet project https://github.com/AndreaCrotti/scrabble/blob/master/test/clj/scrabble/core_test.clj#L114

(and it's pretty awesome actually I have to say)