Data commit

Task/Inverted-index/Clojure/inverted-index.clj

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+(ns inverted-index.core
+  (:require [clojure.set :as sets]
+            [clojure.java.io :as io]))
+
+(def pattern #"\w+")     ; Java regex for a raw term: here a substring of alphanums
+(defn normalize [match] (.toLowerCase match))  ; normalization of a raw term
+
+(defn term-seq [text] (map normalize (re-seq pattern text)))
+
+(defn set-assoc
+  "Produces map with v added to the set associated with key k in map m"
+  [m k v] (assoc m k (conj (get m k #{}) v)))
+
+(defn index-file [index file]
+  (with-open [reader (io/reader file)]
+    (reduce
+      (fn [idx term] (set-assoc idx term file))
+      index
+      (mapcat term-seq (line-seq reader)))))
+
+(defn make-index [files]
+  (reduce index-file {} files))
+
+(defn search [index query]
+  (apply sets/intersection (map index (term-seq query))))