在clojure中,我如何选择并返回集合的子集

Question

如果我有这样的集合

{{:A "a" :B "b"} {:A "a" :B "Goal" } {:A "a" :B "Goal"}}

如何创建一个函数,只返回部分在哪里:B "Goal"？仅含义:

{{:A "a" :B "Goal" } {:A "a" :B "Goal"}}

Answer 1

我修复了你的数据,使其成为3幅地图的矢量.

(def data [{:A "a" :B "b"}
           {:A "a" :B "Goal"}
           {:A "a" :B "Goal"}])

(defn b-goal?
  [item]
  (= (:B item) "Goal") )

(filter b-goal? data) => ({:A "a", :B "Goal"} {:A "a", :B "Goal"})

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