gistfile1.txt

 ;; bigrams key is a word and value 
 ;; is a map of word counts
 ;; merge operation is merging map values with +
 (def bigrams  
   (bucket/new
    {:type :mem
     :merge (partial merge-with +)}))

 ;; For each word, count following words
 (doseq [[before after] 
          (partition-all 2 words)]
    (bucket/merge bigrams 
      before {after 1}))