small performance improvement

src/nal/deriver.clj

@@ -1,7 +1,8 @@
 (ns nal.deriver
   (:require
     [nal.deriver.utils :refer [walk]]
-    [nal.deriver.key-path :refer [mall-paths all-paths path mpath-invariants]]
+    [nal.deriver.key-path :refer [mall-paths all-paths mpath-invariants
+                                  path-with-max-level]]
     [nal.deriver.rules :refer [rule]]))
 
 (defn get-matcher [rules p1 p2]
@@ -15,7 +16,7 @@
       (fn [t1 t2] (mapcat #(% t1 t2) matchers)))))
 
 (def mget-matcher (memoize get-matcher))
-(def mpath (memoize path))
+(def mpath (memoize path-with-max-level))
 (defn generate-conclusions
   [rules {p1 :statement :as t1} {p2 :statement :as t2}]
   (let [matcher (mget-matcher rules (mpath p1) (mpath p2))]

src/nal/deriver/key_path.clj

@@ -8,6 +8,18 @@
       (conj (map path tail) fst))
     :any))
 
+(defn path-with-max-level
+  ([statement] (path-with-max-level 0 statement))
+  ([level statement]
+   (if (coll? statement)
+     (let [[fst & tail] statement]
+       (cons fst
+             (if (> 1 level)
+               (let [next-level (if (= 'conj fst) level (inc level))]
+                 (map #(path-with-max-level next-level %) tail))
+               (repeat (count tail) :any))))
+     :any)))
+
 (defn rule-path
   "Generates detailed pattern for the rule."
   [p1 p2]