entityMap|blocks|key|9b2ja|text|因为Ruby读了下面这行|type|unstyled|depth|inlineStyleRanges|entityRanges|data|asp75|print+"Your+number+is:+#{num}"+&&+return+if+num+>+10|code-block|syntax|javascript|57g9i|像这样|43r9t|print("Your+number+is:+#{num}"+&&+return)+if+num+>+10|bri3|这导致该方法在有机会print任何东西之前使用return。|offset|length|style|CODE|7kaeu|添加一对括号可以帮助Ruby解析所需的顺序：|cfm7r|print("Your+number+is:+#{num}")+%7C%7C+return+if+num+>+10|2qcd7^0|0|0|0|0|A|5|N|6|0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|W|9|@]|A|@]|B|$]]|$2|C|4|D|6|E|8|X|9|@]|A|@]|B|$F|G]]|$2|H|4|I|6|7|8|Y|9|@]|A|@]|B|$]]|$2|J|4|K|6|E|8|Z|9|@]|A|@]|B|$F|G]]|$2|L|4|M|6|7|8|10|9|@$N|11|O|12|P|Q]|$N|13|O|14|P|Q]]|A|@]|B|$]]|$2|R|4|S|6|7|8|15|9|@]|A|@]|B|$]]|$2|T|4|U|6|E|8|16|9|@]|A|@]|B|$F|G]]|$2|V|4|-4|6|7|8|17|9|@]|A|@]|B|$]]]]

Because Ruby reads this line

<pre><code>print "Your number is: #{num}" &amp;&amp; return if num &gt; 10
</code></pre>

like this

<pre><code>print("Your number is: #{num}" &amp;&amp; return) if num &gt; 10
</code></pre>

That leads the method to <code>return</code> before it had the chance to <code>print</code> anything.

Adding a pair of parenthesis helps Ruby to resolve the desired order:

<pre><code>print("Your number is: #{num}") || return if num &gt; 10
</code></pre>

entityMap|blocks|key|b6j|text|def+foo(num)
+++puts(num+>+10+?+"Your+number+is:+#{num}"+:+"Number+too+small")
end|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|2rbqh|我认为这是一种更简洁的方式，使用If三元。希望这能有所帮助|unstyled|7fejd^0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|I|9|@]|A|@]|B|$C|D]]|$2|E|4|F|6|G|8|J|9|@]|A|@]|B|$]]|$2|H|4|-4|6|G|8|K|9|@]|A|@]|B|$]]]]

<pre><code>def foo(num)
 puts(num &gt; 10 ? "Your number is: #{num}" : "Number too small")
end
</code></pre>

I think this is the cleaner way to do that, with an If ternary. Hope this helps

entityMap|blocks|key|eo22h|text|只是出于好奇：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|7nfu4|def+foo(num)
++print+case+num
++++++++when+-Float::INFINITY...10+then+"Number+too+small"
++++++++else+"Your+number+is:+#{num}"
++++++++end
end|code-block|syntax|javascript|1l4k1^0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|I|9|@]|A|@]|B|$]]|$2|C|4|D|6|E|8|J|9|@]|A|@]|B|$F|G]]|$2|H|4|-4|6|7|8|K|9|@]|A|@]|B|$]]]]

entityMap|blocks|key|bno46|text|执行一行if语句的另一种方法是使用;|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1gqao|def+foo(num)
++if+num+<+10;+print+"Your+number+is:+#{num}"+&&+return;+end
++print+"Number+too+small"
end|code-block|syntax|javascript|826t0^0|H|1|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|M|9|@$A|N|B|O|C|D]]|E|@]|F|$]]|$2|G|4|H|6|I|8|P|9|@]|E|@]|F|$J|K]]|$2|L|4|-4|6|7|8|Q|9|@]|E|@]|F|$]]]]

One more way to do one line if statements is with <code>;</code>

<pre><code>def foo(num)
 if num &lt; 10; print "Your number is: #{num}" &amp;&amp; return; end
 print "Number too small"
end
</code></pre>

entityMap|blocks|key|eug3e|text|您有一个可以使用括号修复的优先级问题。但是，由于您试图表达控制流，因此应该使用控制流运算符and和or，而不是布尔运算符&&和%7C%7C。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|krfu|这个成语的工作原理是这样的：(仅举个例子，它并不局限于return和fail)|cv9js|do_something+and+return+"it+worked"|code-block|syntax|javascript|c5fab|或者：|disd9|do_something+or+fail+"it+didn't+work"|c1n7j|它允许您根据第一个表达式是否成功来计算第二个表达式。do_something应该在成功的情况下返回真值，在失败的情况下返回假值。|60g7j|然而，print总是返回nil，所以在这方面它不会像预期的那样工作。你必须颠倒逻辑：|ccdhq|print+"Your+number+is:+#{num}"+or+return|ad7kk|但这不再是自然而然的了，不是吗？此外，因为print永远不会返回真值，所以总是调用return。你实际上想要：|2t43p|print+"Your+number+is:+#{num}"
return|d84jk|因此，我会简单地写下：|ckjjg|def+foo(num)
++if+num+>+10
++++puts+"Your+number+is:+#{num}"
++else
++++puts+"Number+too+small"
++end
end|fnj1c^0|19|3|1D|2|1O|2|1R|2|0|R|6|Y|4|0|0|0|0|Q|C|0|3|5|C|3|0|0|L|5|15|6|0|0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|16|9|@$A|17|B|18|C|D]|$A|19|B|1A|C|D]|$A|1B|B|1C|C|D]|$A|1D|B|1E|C|D]]|E|@]|F|$]]|$2|G|4|H|6|7|8|1F|9|@$A|1G|B|1H|C|D]|$A|1I|B|1J|C|D]]|E|@]|F|$]]|$2|I|4|J|6|K|8|1K|9|@]|E|@]|F|$L|M]]|$2|N|4|O|6|7|8|1L|9|@]|E|@]|F|$]]|$2|P|4|Q|6|K|8|1M|9|@]|E|@]|F|$L|M]]|$2|R|4|S|6|7|8|1N|9|@$A|1O|B|1P|C|D]]|E|@]|F|$]]|$2|T|4|U|6|7|8|1Q|9|@$A|1R|B|1S|C|D]|$A|1T|B|1U|C|D]]|E|@]|F|$]]|$2|V|4|W|6|K|8|1V|9|@]|E|@]|F|$L|M]]|$2|X|4|Y|6|7|8|1W|9|@$A|1X|B|1Y|C|D]|$A|1Z|B|20|C|D]]|E|@]|F|$]]|$2|Z|4|10|6|K|8|21|9|@]|E|@]|F|$L|M]]|$2|11|4|12|6|7|8|22|9|@]|E|@]|F|$]]|$2|13|4|14|6|K|8|23|9|@]|E|@]|F|$L|M]]|$2|15|4|-4|6|7|8|24|9|@]|E|@]|F|$]]]]

You have a precedence issue which can be fixed using parentheses. But since you are trying to express a control flow, you should use the control flow operators <code>and</code> and <code>or</code> instead of the boolean operators <code>&amp;&amp;</code> and <code>||</code>.

The idiom works like this: (just examples, it's not limited to <code>return</code> and <code>fail</code>)

<pre><code>do_something and return "it worked"
</code></pre>

or:

<pre><code>do_something or fail "it didn't work"
</code></pre>

It allows you to evaluate a second expression depending on whether the first expression succeeded or not. <code>do_something</code> is supposed to return a truthy value in case of success and a falsey value in case of failure.

<code>print</code> however always returns <code>nil</code>, so it doesn't work as expected in this regard. You would have to reverse the logic:

<pre><code>print "Your number is: #{num}" or return
</code></pre>

But this doesn't read naturally any more, does it? Beside, <code>return</code> is always invoked, because <code>print</code> will never return a truthy value. You actually want:

<pre><code>print "Your number is: #{num}"
return
</code></pre>

I would therefore simply write:

<pre><code>def foo(num)
 if num &gt; 10
 puts "Your number is: #{num}"
 else
 puts "Number too small"
 end
end
</code></pre>

entityMap|0|type|LINK|mutability|MUTABLE|data|url|https://en.wikipedia.org/wiki/Guard_(computer_science%2529|blocks|key|c3ef7|text|因为print+(和puts)返回nil，所以它也能正常工作：|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|4e7dd|def+foo(num)
++return+print+"Your+number+is:+#{num}"+if+num+>+10
++print+"Number+too+small"
end|code-block|syntax|javascript|76vr1|为了显示更清晰的意图，请将保护从句(https://en.wikipedia.org/wiki/Guard_(computer_science%2529)放在第一位：|81she|def+foo(num)
++return+print+"Number+too+small"+if+num+<=+10
++print+"Your+number+is:+#{num}"
end|bpts4|示例：|fgk09|>+foo+47
Your+number+is:+47=>+nil
>+foo+7
Number+too+small=>+nil|d4ori^0|2|5|A|4|H|3|0|0|I|1K|0|0|0|0|0^^$0|$1|$2|3|4|5|6|$7|8]]]|9|@$A|B|C|D|2|E|F|10|G|@$H|11|I|12|J|K]|$H|13|I|14|J|K]|$H|15|I|16|J|K]]|L|@]|6|$]]|$A|M|C|N|2|O|F|17|G|@]|L|@]|6|$P|Q]]|$A|R|C|S|2|E|F|18|G|@]|L|@$H|19|I|1A|A|1B]]|6|$]]|$A|T|C|U|2|O|F|1C|G|@]|L|@]|6|$P|Q]]|$A|V|C|W|2|E|F|1D|G|@]|L|@]|6|$]]|$A|X|C|Y|2|O|F|1E|G|@]|L|@]|6|$P|Q]]|$A|Z|C|-4|2|E|F|1F|G|@]|L|@]|6|$]]]]

Since <code>print</code> (and <code>puts</code>) returns <code>nil</code>, this works just as well:
<pre><code>def foo(num)
 return print &quot;Your number is: #{num}&quot; if num &gt; 10
 print &quot;Number too small&quot;
end
</code></pre>
And to show clearer intention, place the <a href="https://en.wikipedia.org/wiki/Guard_(computer_science)" rel="nofollow noreferrer">guard clause</a> first:
<pre><code>def foo(num)
 return print &quot;Number too small&quot; if num &lt;= 10
 print &quot;Your number is: #{num}&quot;
end
</code></pre>
Examples:
<pre><code>&gt; foo 47
Your number is: 47=&gt; nil
&gt; foo 7
Number too small=&gt; nil
</code></pre>

How can I print a message and then return from a function in ruby?

<pre><code>2.3.4 :038 &gt; def foo(num)
2.3.4 :039?&gt; print "Your number is: #{num}" &amp;&amp; return if num &gt; 10
2.3.4 :040?&gt; print "Number too small"
2.3.4 :041?&gt; end
 =&gt; :foo
2.3.4 :042 &gt; foo(47)
 =&gt; nil
2.3.4 :043 &gt; foo(7)
Number too small =&gt; nil
2.3.4 :044 &gt;
</code></pre>

When I called foo with <code>47</code> why didn't I got <code>Your number is: 47</code> in output?

PS: This function can be written in other simpler ways also, I just wanted to express my doubt via this function.

Ruby: how to combine puts and return inside if condition?

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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 如何打印一条消息，然后从ruby中的函数返回？ 2.3.4 :038 > def foo(num)2.3.4 :039?>   print "Your number is: #{num}" && return if num > 102.3.4 :040?>   print "Number too small"2.3....

问Ruby:如何在if条件中组合put和return？
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问Ruby:如何在if条件中组合put和return？EN