如何创建从字符串而不是文件或URL读取的输入流

Question

我想绑定*in*到从字符串而不是"真实"输入流读取的流.我该怎么做呢？

Answer 1

退房with-in-str:

http://clojure.github.com/clojure/clojure.core-api.html#clojure.core/with-in-str

ClojureDocs有一个使用它的例子:

;; Given you have a function that will read from *in*
(defn prompt [question]
  (println question)
  (read-line))

user=> (prompt "How old are you?")
How old are you?
34                   ; <== This is what you enter
"34"                 ; <== This is returned by the function

;; You can now simulate entering your age at the prompt by using with-in-str

user=> (with-in-str "34" (prompt "How old are you?"))
How old are you?
"34"                 ; <== The function now returns immediately 

Answer 2

这是我最终所做的示例代码。这个想法是一个简单的服务器读取/打印循环函数，它接受输入和输出流。我的问题是如何为这样的函数生成测试流，我认为字符串函数就可以了。相反，这就是我所需要的：

(ns test
    (:use [clojure.java.io :only [reader writer]]))
(def prompt ">")
(defn test-client [in out]
  (binding [*in* (reader in)
            *out* (writer out)]
           (print prompt) (flush)

(loop [input (read-line)]
             (when input
               (println (str "OUT:" input))
               (print prompt) (flush)
               (if (not= input "exit\n") (recur (read-line)) )
               ))))
(def client-stream (java.io.PipedWriter.))
(def r (java.io.BufferedReader. (java.io.PipedReader. client-stream)))
(doto (Thread. #(do (test-client r *out*))) .start)

(.write client-stream "test\n")