blocks|key|3788501|text|你在那里有两个括号。试试这个：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3788502|(defn+-main
++[]
++(defn+CHEESE
++++[]
++++(str+"Hello+World"))
++(CHEESE))|code-block|syntax|javascript|3788503|当然，您必须调用-main，否则您将什么也看不到：|offset|length|style|CODE|3788504|(defn+-main
++[]
++(defn+CHEESE
++++[]
++++(str+"Hello+World"))
++(CHEESE))
=>+#'com.playground.core/-main
(-main)
=>+"Hello+World"|3788505|我看到您在另一个函数中定义了一个函数。为此，您应该使用let或letfn。|3788506|entityMap^0|0|0|8|5|0|0|R|3|V|5|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|U|8|@$I|V|J|W|K|L]]|9|@]|A|$]]|$1|M|3|N|5|D|7|X|8|@]|9|@]|A|$E|F]]|$1|O|3|P|5|6|7|Y|8|@$I|Z|J|10|K|L]|$I|11|J|12|K|L]]|9|@]|A|$]]|$1|Q|3|-4|5|6|7|13|8|@]|9|@]|A|$]]]|R|$]]

You have a double parentheses there. Try this:
<pre><code>(defn -main
 []
 (defn CHEESE
 []
 (str &quot;Hello World&quot;))
 (CHEESE))
</code></pre>
Of course your MUST call <code>-main</code>, otherwise you'll see nothing:
<pre><code>(defn -main
 []
 (defn CHEESE
 []
 (str &quot;Hello World&quot;))
 (CHEESE))
=&gt; #'com.playground.core/-main
(-main)
=&gt; &quot;Hello World&quot;
</code></pre>
I see your define a function inside another function. You should use <code>let</code> or <code>letfn</code> for this purpose.

blocks|key|3788538|text|为项目启动REPL不会运行-main。运行您的程序将产生以下结果：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|3788539|Execution+error+(ArityException)+at+com.playground.core/-main+(core.clj:6).
Wrong+number+of+args+(1)+passed+to:+com.playground.core/-main/CHEESE--177|code-block|syntax|javascript|3788540|这是怎么回事？|3788541|3788542|+defn表单在com.playground.core命名空间中创建和注册一个名为CHEESE的函数。|ordered-list-item|3788543|+defn表单返回创建的var，它的计算结果是包含((defn+...)+(CHEESE))表单的CHEESE函数应用于(CHEESE)，这是计算CHEESE函数时没有参数的结果，H+216H+117.是字符串"Hello+World".|3788544|。|3788545|参数是什么并不重要，因为CHEESE没有第1次调用:您不能将它应用于任何参数。|3788546|通过将defn+for+CHEESE从-main中提取出来，您可以获得同样的(坏的)效果。当我们完成这个任务时，让我们放弃str，它没有任何效果：|3788547|(defn+CHEESE+[]
++"Hello+World")

(defn+-main+[]
++(CHEESE+(CHEESE)))

Execution+error+(ArityException)+at+com.playground.core/-main+(core.clj:8).
Wrong+number+of+args+(1)+passed+to:+com.playground.core/CHEESE|3788548|为了纠正这个问题，我们简单地删除了(CHEESE)参数：|3788549|(defn+-main+[]
++(CHEESE))|3788550|生产..。|3788551|Process+finished+with+exit+code+0|3788552|没有返回值，但至少它运行。但是如果我们在REPL中评估(-main)，.|3788553|(-main)
=>+"Hello+World"|3788554|那里。|3788555|entityMap^0|D|5|0|0|0|0|1|4|8|J|15|6|0|1|4|P|L|1D|6|1O|8|21|6|2I|A|2X|D|0|0|C|6|0|3|4|C|6|J|5|1P|3|0|0|H|8|0|0|0|0|R|7|0|0|0^^$0|@$1|2|3|4|5|6|7|1G|8|@$9|1H|A|1I|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|1J|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|1K|8|@]|D|@]|E|$]]|$1|M|3|-4|5|6|7|1L|8|@]|D|@]|E|$]]|$1|N|3|O|5|P|7|1M|8|@$9|1N|A|1O|B|C]|$9|1P|A|1Q|B|C]|$9|1R|A|1S|B|C]]|D|@]|E|$]]|$1|Q|3|R|5|P|7|1T|8|@$9|1U|A|1V|B|C]|$9|1W|A|1X|B|C]|$9|1Y|A|1Z|B|C]|$9|20|A|21|B|C]|$9|22|A|23|B|C]|$9|24|A|25|B|C]|$9|26|A|27|B|C]]|D|@]|E|$]]|$1|S|3|T|5|6|7|28|8|@]|D|@]|E|$]]|$1|U|3|V|5|6|7|29|8|@$9|2A|A|2B|B|C]]|D|@]|E|$]]|$1|W|3|X|5|6|7|2C|8|@$9|2D|A|2E|B|C]|$9|2F|A|2G|B|C]|$9|2H|A|2I|B|C]|$9|2J|A|2K|B|C]]|D|@]|E|$]]|$1|Y|3|Z|5|H|7|2L|8|@]|D|@]|E|$I|J]]|$1|10|3|11|5|6|7|2M|8|@$9|2N|A|2O|B|C]]|D|@]|E|$]]|$1|12|3|13|5|H|7|2P|8|@]|D|@]|E|$I|J]]|$1|14|3|15|5|6|7|2Q|8|@]|D|@]|E|$]]|$1|16|3|17|5|H|7|2R|8|@]|D|@]|E|$I|J]]|$1|18|3|19|5|6|7|2S|8|@$9|2T|A|2U|B|C]]|D|@]|E|$]]|$1|1A|3|1B|5|H|7|2V|8|@]|D|@]|E|$I|J]]|$1|1C|3|1D|5|6|7|2W|8|@]|D|@]|E|$]]|$1|1E|3|-4|5|6|7|2X|8|@]|D|@]|E|$]]]|1F|$]]

Starting a REPL for the project does not run <code>-main</code>. Running your program produces the following:
<pre><code>Execution error (ArityException) at com.playground.core/-main (core.clj:6).
Wrong number of args (1) passed to: com.playground.core/-main/CHEESE--177
</code></pre>
What is happening?
<ol>
<li>The <code>defn</code> form creates and registers a function under the name
<code>CHEESE</code> in the <code>com.playground.core</code> namespace.</li>
<li>The <code>defn</code> form returns the created var, which evaluates to the
function.</li>
<li>The containing <code>((defn ...) (CHEESE))</code> form applies the <code>CHEESE</code> function to
<code>(CHEESE)</code>, the result of evaluating the <code>CHEESE</code> function without
arguments,</li>
<li>... which is the string <code>&quot;Hello World&quot;</code>.</li>
</ol>
It doesn't matter what the argument is, because <code>CHEESE</code> has no arity 1 invocation: you can't apply it to any argument.
You can get the same (bad) effect more simply by pulling the <code>defn</code> for <code>CHEESE</code> out of <code>-main</code>. While we're at it, let's drop the <code>str</code>, which has no effect:
<pre><code>(defn CHEESE []
 &quot;Hello World&quot;)

(defn -main []
 (CHEESE (CHEESE)))

Execution error (ArityException) at com.playground.core/-main (core.clj:8).
Wrong number of args (1) passed to: com.playground.core/CHEESE
</code></pre>
To put it right, we simply drop the <code>(CHEESE)</code>argument:
<pre><code>(defn -main []
 (CHEESE))
</code></pre>
producing ...
<pre><code>Process finished with exit code 0
</code></pre>
No returned value, but at least it ran. But if we evaluate <code>(-main)</code> in a REPL, ...
<pre><code>(-main)
=&gt; &quot;Hello World&quot;
</code></pre>
There.

blocks|key|4320026|text|事实上，这并不是完全错误的。这种返回是“申报的返回”。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4320027|例如，您在-main命名空间中定义了一个com.playground.core。|offset|length|style|CODE|4320028|返回是此声明#'com.playground.core/-main的符号。|4320029|要打印Hello+world消息，需要在声明后调用函数CHEESE。|4320030|​|4320031|📷|atomic|4320032|4320033|所以..。关于双括号，这不是好事，但不影响他。另一点是函数名，它也不好。考虑用烤肉串。|4320034|您还可以考虑更显式地保留函数声明。类似这样的事情；|4320035|(ns+com.playground.core
++(:gen-class))

(defn+CHEESE+[]+(str+"Hello+World"))

(defn+-main+[]
++(CHEESE))|code-block|syntax|javascript|4320036|但同时你也没在打印“你好世界”。您只声明一个返回字符串类型的函数(奶酪)。|4320037|要打印，您需要调用一个打印函数。|4320038|(ns+com.playground.core
++(:gen-class))

(defn+hello+[]+(str+"Hello+World"))

(defn+-main+[]
++(print+(hello)))|4320039|我做了声明的演变来更好地解释|4320040|4320041|4320042|4320043|因此，可以使用let+alternative和threading+macros改进代码。|4320044|考虑使用https://kimh.github.io/clojure-by-example/和https://tryclojure.org/更好地理解这些选项:)|4320045|entityMap|0|IMAGE|mutability|IMMUTABLE|imageUrl|https://developer.qcloudimg.com/http-save/yehe-900000/a2e780173e86f6b782fe0629310a0bf1.png|imageAlt|1|https://developer.qcloudimg.com/http-save/yehe-900000/aa46998612d0c5e829fc40d98de7ca86.png|2|LINK|MUTABLE|url|https://kimh.github.io/clojure-by-example/|3|https://tryclojure.org/^0|0|5|5|K|J|0|6|R|0|3|B|R|6|0|0|0|1|0|0|0|0|0|0|0|0|0|0|0|0|1|1|0|0|7|3|N|G|0|4|16|2|1B|N|3|0^^$0|@$1|2|3|4|5|6|7|1X|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|1Y|8|@$D|1Z|E|20|F|G]|$D|21|E|22|F|G]]|9|@]|A|$]]|$1|H|3|I|5|6|7|23|8|@$D|24|E|25|F|G]]|9|@]|A|$]]|$1|J|3|K|5|6|7|26|8|@$D|27|E|28|F|G]|$D|29|E|2A|F|G]]|9|@]|A|$]]|$1|L|3|M|5|6|7|2B|8|@]|9|@]|A|$]]|$1|N|3|O|5|P|7|2C|8|@]|9|@$D|2D|E|2E|1|2F]]|A|$]]|$1|Q|3|M|5|6|7|2G|8|@]|9|@]|A|$]]|$1|R|3|S|5|6|7|2H|8|@]|9|@]|A|$]]|$1|T|3|U|5|6|7|2I|8|@]|9|@]|A|$]]|$1|V|3|W|5|X|7|2J|8|@]|9|@]|A|$Y|Z]]|$1|10|3|11|5|6|7|2K|8|@]|9|@]|A|$]]|$1|12|3|13|5|6|7|2L|8|@]|9|@]|A|$]]|$1|14|3|15|5|X|7|2M|8|@]|9|@]|A|$Y|Z]]|$1|16|3|17|5|6|7|2N|8|@]|9|@]|A|$]]|$1|18|3|M|5|6|7|2O|8|@]|9|@]|A|$]]|$1|19|3|O|5|P|7|2P|8|@]|9|@$D|2Q|E|2R|1|2S]]|A|$]]|$1|1A|3|M|5|6|7|2T|8|@]|9|@]|A|$]]|$1|1B|3|1C|5|6|7|2U|8|@$D|2V|E|2W|F|G]|$D|2X|E|2Y|F|G]]|9|@]|A|$]]|$1|1D|3|1E|5|6|7|2Z|8|@]|9|@$D|30|E|31|1|32]|$D|33|E|34|1|35]]|A|$]]|$1|1F|3|-4|5|6|7|36|8|@]|9|@]|A|$]]]|1G|$1H|$5|1I|1J|1K|A|$1L|1M|1N|-4]]|1O|$5|1I|1J|1K|A|$1L|1P|1N|-4]]|1Q|$5|1R|1J|1S|A|$1T|1U]]|1V|$5|1R|1J|1S|A|$1T|1W]]]]

Actually, It's not exactly wrong.
This return is the &quot;return of declaration&quot;.
For example, you defined a <code>-main</code> in the <code>com.playground.core</code> namespace.
The return is the symbol of this declaration <code>#'com.playground.core/-main</code>
To print the <code>Hello world</code> message you need to call the function <code>CHEESE</code> after the declaration.
<a href="https://i.stack.imgur.com/frtvy.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/frtvy.png" alt="enter image description here" /></a>
So... about double parenthesis, it's not good, but not impact hehe.
Another point is the function name, it's not good too. Consider using kebab-case.
You also consider keeping the function declaration more explicitly. Something like that;
<pre><code>(ns com.playground.core
 (:gen-class))

(defn CHEESE [] (str &quot;Hello World&quot;))

(defn -main []
 (CHEESE))
</code></pre>
But also did it you're not printing the Hello world. Your only declaring a function (CHEESE) that returns a String type.
To print, you need to call a print function.
<pre><code>(ns com.playground.core
 (:gen-class))

(defn hello [] (str &quot;Hello World&quot;))

(defn -main []
 (print (hello)))
</code></pre>
I did the evolution of declarations to explain better
<a href="https://i.stack.imgur.com/rzc8v.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/rzc8v.png" alt="enter image description here" /></a>
So, you can improve the code using the <code>let</code> alternative and the <code>threading macros</code>
Consider use the <a href="https://kimh.github.io/clojure-by-example/" rel="nofollow noreferrer">https://kimh.github.io/clojure-by-example/</a> and <a href="https://tryclojure.org/" rel="nofollow noreferrer">https://tryclojure.org/</a> to understand these options better :)

I just started learning Clojure and I have my own Clojure script but it's not returning the output that I am hoping for (<code>Hello World</code>). Here is my code:
<pre class="lang-clj prettyprint-override"><code>(ns com.playground.core
 (:gen-class))

(defn -main 
 [] 
 ((defn CHEESE
 []
 (str &quot;Hello World&quot;))

 (CHEESE)))
</code></pre>
This is the output that I get in the REPL:
<pre><code>clj꞉com.playground.core꞉&gt; 
#'com.playground.core/-main
</code></pre>
I want to see <code>Hello World</code> in the output.

clojure returning hello world and nothing in the output

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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我刚开始学习Clojure，我有自己的Clojure脚本，但是它没有返回我所希望的输出(Hello World)。这是我的代码：(ns com.playground.core  (:gen-class))(defn -main   []   ((defn CHEESE     []     (str "Hello Wo...

问clojure返回hello world，输出中没有任何内容
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问clojure返回hello world，输出中没有任何内容EN