我是Clojure的新手，因此尝试使用clojuredocs.org中的示例数据。
;; Data
(def scenes [{:subject "Frankie"
:action "say"
:object "relax"}
{:subject "Lucy"
:action "loves"
:object "Clojure"}
{:subject "Rich"
:action "tries"
:object "a new conditioner"}])
(defn play [scenes n]
"Play a scene"
(->>
scenes
(#(get % n))
((juxt :subject :action :object))
(interpose " ")
(apply str)))
该play功能可以正常工作：
my-stuff.core> (play scenes 0)
"Frankie say relax"
my-stuff.core> (play scenes 1)
"Lucy loves Clojure"
my-stuff.core> (play scenes 2)
"Rich tries a new conditioner"
此play-all功能不起作用：
(defn play-all [scenes]
"Play all the scenes"
(let [x (count scenes)]
(for [n (range x)]
(map play scenes n ))))
如何更正此play-all功能，即如何将播放功能应用于数据范围？
map迭代一个（或多个）集合以产生一个序列。for根据列表理解建立一个序列。你的情况，你可以使用一个或另一个。
就分解而言，实际上具有播放一个场景的功能将是有意义的：
(defn play-one [scene]
"Play a scene"
(->>
scene
((juxt :subject :action :object))
(interpose " ")
(apply str)))
然后播放第n个可以使用先例定义：
(defn play-nth [scenes n]
"Play the n(th) scene"
(->
scenes
(#(get % n))
play-one))
您可以通过多种方式播放所有场景：
(defn play-all-map1 [scenes]
"Play all the scenes"
(map (partial play-nth scenes) (range (count scenes))))
但是您可以真正简化一下，因为您不需要，range因为scenes可以将其视为一个序列（假设您对索引不感兴趣）：
(defn play-all-map2 [scenes]
"Play all the scenes with map"
(map play-one scenes))
并带有for：
(defn play-all-for [scenes]
"Play all the scenes with for"
(for [scene scenes]
(play-one scene)))
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