clojure - 如何在 Clojure 中添加这个哈希表？

Question

我有一个文档哈希，它是这样的引用:

(def *document-hash* (ref (hash-map)))  

看起来像这样

 {"documentid" {:term-detail {"term1" count1 ,"term2" count2},  "doclen" 33}}}

如何添加到这个哈希表？现在我已经

(defn add-doc-hash [docid  term-number count]
  (dosync (alter *document-hash*
    (fn [a-hash]
      (assoc a-hash docid {:term-detail  
        (assoc ((a-hash docid)) :term-detail) term-number count), :doclen 33))))))

• 我想更新文档的术语详细信息
• 每次出现新术语时，我都想获取术语详细信息并更新术语及其计数
• 最初哈希为空

但这会引发空指针异常，因为当我尝试添加术语编号时，不会创建术语详细信息哈希。

Answer 1

user> (def x (ref {"documentid" {:term-detail {"term1" 1 ,"term2" 2},  "doclen" 33}}))
#'user/x
user> (dosync (alter x assoc-in ["documentid" :term-detail "term3"] 0))
{"documentid" {:term-detail {"term3" 0, "term1" 1, "term2" 2}, "doclen" 33}}
user> (dosync (alter x update-in ["documentid" :term-detail "term3"] inc))
{"documentid" {:term-detail {"term3" 1, "term1" 1, "term2" 2}, "doclen" 33}}