在Clojure中以功能方式重寫此修剪功能

我有這個功能（摘自program），我想以更具吸引力/功能/慣用的方式重寫。
它應該從s表達式中刪除任何不必要的空格。在Clojure中以功能方式重寫此修剪功能

(defn trim 
    " Trim whitespace from code: 
     (trim (trim \" d ' ( print ( + 1 1) )\") 
    ==> d '(print (+ 1 1)) 
    The replaced string is passed repeatedly to every call. 
    Functional version 
" 
    [string] 
    (clojure.string/replace 
    (clojure.string/replace 
    (clojure.string/replace 
    (clojure.string/replace 
     (clojure.string/replace 
     (clojure.string/replace 
     (clojure.string/replace 
     (clojure.string/replace 
      (clojure.string/replace 
      (clojure.string/replace 
      string #"([^\\(\[{@~`'])(\(|\[|\{)" "$1 $2") 
      #"(\)|\]|})(\[|\(|\{)" "$1 $2") 
      #"[ \t]*(\)|\]|\})" "$1") 
     #"[ \t]{2,}" " ") 
     #"(\)|\]|\})[ \t]*(?=(\)|\]|\}))" "$1") 
     #"(\(|\[|\{)[ \t]*(?=(\(|\[|\{))" "$1") 
     #"^[ \t]*" "") 
    #"(\\\{|\\\(|\\\[) " "$1 ") 
    #"(\{|\(|\[) " "$1") 
    #" ('|`) (\(|\[|\{)" " $1$2"))

我不是很滿意，它看起來像現在，因爲它很難弄清楚它是如何工作的第一眼（佈局可能是問題），如果我要會造成問題的辦法曾經想要添加更多的正則表達式/替換。

這裏的另一個版本，更友好（和必要的）和作品，但相貌平庸：

(defn trim1 
    " Not so functional version" 
    [raw-string] 
    (def string (atom raw-string)) 
    (reset! string (clojure.string/replace @string #"([^\\(\[{@~`'])(\(|\[|\{)" "$1 $2")) 
    (reset! string (clojure.string/replace @string #"(\)|\]|})(\[|\(|\{)" "$1 $2")) 
    (reset! string (clojure.string/replace @string #"[ \t]*(\)|\]|\})" "$1")) 
    (reset! string (clojure.string/replace @string #"[ \t]{2,}" " ")) 
    (reset! string (clojure.string/replace @string #"(\)|\]|\})[ \t]*(?=(\)|\]|\}))" "$1")) 
    (reset! string (clojure.string/replace @string #"(\(|\[|\{)[ \t]*(?=(\(|\[|\{))" "$1")) 
    (reset! string (clojure.string/replace @string #"^[ \t]*" "")) 
    (reset! string (clojure.string/replace @string #"(\\\{|\\\(|\\\[) " "$1 ")) 
    (reset! string (clojure.string/replace @string #"(\{|\(|\[) " "$1")) 
    (reset! string (clojure.string/replace @string #" ('|`) (\(|\[|\{)" " $1$2")))

我希望的，看起來像一個解決方案：

商店正則表達式和關聯列表中的替換：['(#"^[ \t]*" "")]
然後做類似(reduce trim-fn replacement-list string)

如果可以實現，reduce部分將非常酷。但是，如果不可能的話，我會歡迎任何比這兩個更好的解決方案。

來源

2013-12-14 Segfault

(def trim-patterns 
    [[#"([^\\(\[{@~`'])(\(|\[|\{)" "$1 $2"] 
    [#"(\)|\]|})(\[|\(|\{)" "$1 $2"] 
    [#"[ \t]*(\)|\]|\})" "$1"] 
    [#"[ \t]{2,}" " "] 
    [#"(\)|\]|\})[ \t]*(?=(\)|\]|\}))" "$1"] 
    [#"(\(|\[|\{)[ \t]*(?=(\(|\[|\{))" "$1"] 
    [#"^[ \t]*" ""] 
    [#"(\\\{|\\\(|\\\[) " "$1 "] 
    [#"(\{|\(|\[) " "$1"] 
    [#" ('|`) (\(|\[|\{)" " $1$2"]]) 

(defn trim 
    [s] 
    (reduce 
    (fn [s [match replacement]] 
     (clojure.string/replace s match replacement)) 
    s trim-patterns))

來源

2013-12-14 18:47:06 Beyamor

在Clojure中以功能方式重寫此修剪功能

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