blocks|key|1037641|text|因为如果你这样做了：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1037642|assert_equal+true,+all_symbols.include?(:test_method_names_become_symbols)|code-block|syntax|javascript|1037643|它可能(取决于你的ruby实现)自动为真，因为:test_method_names_become_symbols创建了这个符号。参见this+bug+report。|offset|length|style|CODE|1037644|entityMap|0|LINK|mutability|MUTABLE|url|https://github.com/neo/ruby_koans/issues/22^0|0|0|N|X|1U|F|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|V|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|W|8|@$I|X|J|Y|K|L]]|9|@$I|Z|J|10|1|11]]|A|$]]|$1|M|3|-4|5|6|7|12|8|@]|9|@]|A|$]]]|N|$O|$5|P|Q|R|A|$S|T]]]]

Because if you do:

<pre><code>assert_equal true, all_symbols.include?(:test_method_names_become_symbols)
</code></pre>

It may (depending on your ruby implementation) automatically be true, because <code>:test_method_names_become_symbols</code> creates the symbol. See <a href="https://github.com/neo/ruby_koans/issues/22" rel="noreferrer">this bug report</a>.

blocks|key|822731|text|上面的两个答案都是正确的，但鉴于Karthik上面的问题，我想我应该发布一个测试，演示如何准确地将符号传递给include方法|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|822732|def+test_you_create_a_new_symbol_in_the_test
++array_of_symbols+=+[]
++array_of_symbols+<<+Symbol.all_symbols
++all_symbols+=+Symbol.all_symbols.map+{%7Cx%7C+x}
++assert_equal+false,+array_of_symbols.include?(:this_should_not_be_in_the_symbols_collection)++#this+works+because+we+stored+all+symbols+in+an+array+before+creating+the+symbol+:this_should_not_be_in_the_symbols_collection+in+the+test
++assert_equal+true,+all_symbols.include?(:this_also_should_not_be_in_the_symbols_collection)+#This+is+the+case+noted+in+previous+answers...here+we've+created+a+new+symbol+(:this_also_should_not_be_in_the_symbols_collection)+in+the+test+and+then+mapped+all+the+symbols+for+comparison.+Since+we+created+the+symbol+before+querying+all_symbols,+this+test+passes.
end|code-block|syntax|javascript|822733|关于Koans的附加说明:如果您不理解任何内容，请使用puts语句和自定义测试。例如，如果您看到：|822734|string+=+"the:rain:in:spain"
words+=+string.split(/:/)|822735|如果不知道words可能是什么，请添加下面这行|822736|puts+words|822737|并在命令行中运行rake。同样，像我在上面添加的测试在理解Ruby的一些细微差别方面也很有帮助。|822738|entityMap^0|1I|7|0|0|R|4|0|0|5|5|0|0|8|4|0^^$0|@$1|2|3|4|5|6|7|W|8|@$9|X|A|Y|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|Z|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|10|8|@$9|11|A|12|B|C]]|D|@]|E|$]]|$1|M|3|N|5|H|7|13|8|@]|D|@]|E|$I|J]]|$1|O|3|P|5|6|7|14|8|@$9|15|A|16|B|C]]|D|@]|E|$]]|$1|Q|3|R|5|H|7|17|8|@]|D|@]|E|$I|J]]|$1|S|3|T|5|6|7|18|8|@$9|19|A|1A|B|C]]|D|@]|E|$]]|$1|U|3|-4|5|6|7|1B|8|@]|D|@]|E|$]]]|V|$]]

Both answers above are correct, but in light of Karthik's question above I thought I would post a test that illustrates how one might accurately pass a symbol to the <code>include</code> method

<pre><code>def test_you_create_a_new_symbol_in_the_test
 array_of_symbols = []
 array_of_symbols &lt;&lt; Symbol.all_symbols
 all_symbols = Symbol.all_symbols.map {|x| x}
 assert_equal false, array_of_symbols.include?(:this_should_not_be_in_the_symbols_collection) #this works because we stored all symbols in an array before creating the symbol :this_should_not_be_in_the_symbols_collection in the test
 assert_equal true, all_symbols.include?(:this_also_should_not_be_in_the_symbols_collection) #This is the case noted in previous answers...here we've created a new symbol (:this_also_should_not_be_in_the_symbols_collection) in the test and then mapped all the symbols for comparison. Since we created the symbol before querying all_symbols, this test passes.
end
</code></pre>

An additional note about the Koans: make use of <code>puts</code> statements as well as custom tests if you don't understand anything. For instance, if you see:

<pre><code>string = "the:rain:in:spain"
words = string.split(/:/)
</code></pre>

and have no idea what <code>words</code> might be, add the line 

<pre><code>puts words
</code></pre>

and run <code>rake</code> at the command line. Likewise, tests like the one I added above can be helpful in terms of understanding some of the nuances of Ruby.

I'm referring to this test in about_symbols.rb in Ruby Koans
<a href="https://github.com/edgecase/ruby_koans/blob/master/src/about_symbols.rb#L26" rel="noreferrer">https://github.com/edgecase/ruby_koans/blob/master/src/about_symbols.rb#L26</a>

<pre><code>def test_method_names_become_symbols
 symbols_as_strings = Symbol.all_symbols.map { |x| x.to_s }
 assert_equal true, symbols_as_strings.include?("test_method_names_become_symbols")
end


 # THINK ABOUT IT:
 #
 # Why do we convert the list of symbols to strings and then compare
 # against the string value rather than against symbols?
</code></pre>

Why exactly do we have to convert that list into strings first?

Ruby Koans: Why convert list of symbols to strings

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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我指的是Ruby Koans 的about_symbols.rb中的这个测试def test_method_names_become_symbols  symbols_as_strings = Symbol.all_symbols.map { |x| x.to_s }  assert_equal true, symbo...

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