string - 在 Clojure 中用\* 替换 *

Question

我该如何逃生 "*"至 "\*"在clojure？似乎无法让它工作:
(s/replace "A*B" #"*" "*")生产 "A*B" (当然)
(s/replace "A*B" #"*" "\*")失败:Unsupported escape character: *(s/replace "A*B" #"*" "\\*")生产 "A*B"再次!
(s/replace "A*B" #"*" "\\\*")失败:Unsupported escape character: *再次!
(s/replace "A*B" #"\\\\*" "*")生产 "A\\*B"
我无法让它生产 A\*B有任何想法吗？谢谢

Answer 1

您必须使用 4 个反斜杠:

> (println (clojure.string/replace "A*B" #"\*" "\\\\*"))
A\*B
nil
>  

或者，没有正则表达式，它只是:

> (println (clojure.string/replace "A*B" "*" "\\*"))
A\*B
nil
>  

要将其用作正则表达式模式，请使用 re-pattern 功能:

> (def p (clojure.string/replace "A*B" #"\*" "\\\\*"))
#'sandbox17459/p
> (println p)
A\*B
nil
> (clojure.string/replace "BLA*BLA" (re-pattern p) "UH")
"BLUHLA"
>