为什么我的 clojure 循环返回单个字母而不是整个单词？

Question

我正在尝试循环一组字符串，删除多余的文本。它有效，但太好了。给定这样的输入：

#{"TORCASO,133114,117,0.04,89045.38,99.00,0.00,0.00,0.00,0.00,0.00" "POTOCZNY,98770,170,0.06,87231.39,98.82,0.00,(S),0.00,0.00,(S)"}

我的输出如下所示：

#{\A \C \N \O \P \R \S \T \Y \Z}

但我希望它看起来像这样：

#{"TORCASO" "POTOCZNY"}

这是我的代码：

(defn shorten-string
  [string]
  (first (str/split string #",")))


(defn handle-csv
  [strings]
  (loop [remaining-strings strings final-set #{}]
   (if (empty? remaining-strings)
     final-set
     (let [[part & remaining] remaining-strings]
       (recur remaining
              (into final-set
                    (shorten-string part)))))))

我究竟做错了什么？

Answer 1

使用loop / recurfor 循环应该是你最后的手段——通常有一些更好的函数。在这种情况下，您应该使用map：

(def data #{"TORCASO,133114,117,0.04,89045.38,99.00,0.00,0.00,0.00,0.00,0.00" "POTOCZNY,98770,170,0.06,87231.39,98.82,0.00,(S),0.00,0.00,(S)"})

(defn shorten-string [string]
  (first (clojure.string/split string #",")))

(defn handle-csv [strings]
  (->> strings
       (map shorten-string)
       (into #{})))

（->>是线程最后宏）

例子：

(handle-csv data)
=> #{"TORCASO" "POTOCZNY"}