Merge branch 'master' of https://github.com/crista/exercises-in-programming-style

06-candy-factory/tf-06.clj

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+":";exec java -cp "$HOME/.m2/repository/org/clojure/clojure/1.5.1/clojure-1.5.1.jar" clojure.main $0 $*
+
+; Sort of a hack; Clojure isn't really intended as a scripting language. :-/
+
+(require '[clojure.string :refer [split]]
+         '[clojure.java.io :refer [reader]]
+         '[clojure.pprint :refer [pprint]])
+
+(defn stopwords
+  "Reads a set of comma-separated stopwords from the given filename."
+  [file]
+  (-> file
+      slurp
+      (split #"\s+,\s+")
+      set))
+
+(defn words
+  "Splits a string into a sequence of words."
+  [string]
+  (clojure.string/split string #"[^a-zA-Z]+"))
+
+(defn normalize
+  "Normalizes split words to terms."
+  [word]
+  (.toLowerCase word))
+
+(defn too-short?
+  "Is a word too short for consideration?"
+  [word]
+  (<= (.length word) 2))
+
+; Lazily split the file into lines, explode lines into words, normalize into
+; terms, reject unsuitable candidates, compute frequencies, and take the top
+; 25.
+(with-open [f (reader "../pride-and-prejudice.txt")]
+  (->> f
+       line-seq
+       (mapcat words)
+       (map normalize)
+       (remove too-short?)
+       (remove (stopwords "../stop_words.txt"))
+       frequencies
+       (sort-by second)
+       reverse
+       (take 25)
+       pprint))