fooling around

(defn single? [a]
  (= 1 (count a)))

(defmacro map-check [map-features & predicates]
  (let [symbols  #(->> % (into []) flatten 
                   (filter symbol?) 
                   (into #{}))]
  `(fn [m#]
     (and (map? m#)
          (<= 1 (count (l/run 1 [~@(symbols map-features)]
              (l/featurec m# ~map-features)
             ~@(for [predicate predicates]
                 `(l/project [~@(intersection 
                                  (symbols map-features) 
                                  (symbols predicate))]
                     (l/== true (~@predicate)))
                 ))))))))

(def symbols  #(->> % (into []) flatten 
                   (filter symbol?) 
                   (into #{})))

(defmacro map-features? [m features]
   `(<= 1 (count (l/run 1 [~@(symbols features)]
              (l/featurec ~m ~features)))))

(defmacro map-predicate? [m features predicate]
   `(<= 1 (count (l/run 1 [~@(symbols features)]
              (l/featurec ~m ~features)
              (l/project [~@(intersection 
                      (symbols features) 
                      (symbols predicate))]
                     (l/== true (~@predicate)))             
              ))))