entityMap|blocks|key|6g1uj|text|如果这是有效的结构定义|type|unstyled|depth|inlineStyleRanges|entityRanges|data|cje6e|不，不是。要获取C17+6.7.2.1形式语法的一部分：|1nlq5|结构声明：|463ck|说明符-限定符-列表结构-声明符-列表_opt+;|offset|length|style|CODE|cqbvo|_static_assert-声明|ai1kn|ek032|因此，首先，该结构需要在变量名之前包含一个“说明符-限定符列表”，简单地说就是const+int等内容。由于这不存在，例如，gcc抱怨语法错误：|93hno|错误：'...‘前应有说明符-限定符-列表令牌|fm683|qfue|2.这样的定义的目的是什么(没有定义字段/成员)？|97ra2|1qjir|我猜这要么是伪代码，要么是开发人员的"TODO“，因为他们提交了不能编译的代码，因为它还没有被编写。^0|0|0|0|O|1|0|0|0|13|9|0|0|0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|Z|9|@]|A|@]|B|$]]|$2|C|4|D|6|7|8|10|9|@]|A|@]|B|$]]|$2|E|4|F|6|7|8|11|9|@]|A|@]|B|$]]|$2|G|4|H|6|7|8|12|9|@$I|13|J|14|K|L]]|A|@]|B|$]]|$2|M|4|N|6|7|8|15|9|@]|A|@]|B|$]]|$2|O|4|-4|6|7|8|16|9|@]|A|@]|B|$]]|$2|P|4|Q|6|7|8|17|9|@$I|18|J|19|K|L]]|A|@]|B|$]]|$2|R|4|S|6|7|8|1A|9|@]|A|@]|B|$]]|$2|T|4|-4|6|7|8|1B|9|@]|A|@]|B|$]]|$2|U|4|V|6|7|8|1C|9|@]|A|@]|B|$]]|$2|W|4|-4|6|7|8|1D|9|@]|A|@]|B|$]]|$2|X|4|Y|6|7|8|1E|9|@]|A|@]|B|$]]]]

<blockquote>
<ol>
<li>If this is a valid struct definition</li>
</ol>
</blockquote>
No it isn't. To grab part of the C17 6.7.2.1 formal grammar:
<blockquote>
struct-declaration: 
specifier-qualifier-list struct-declarator-listopt <code>;</code> 
static_assert-declaration
</blockquote>
So to begin with, the struct needs to contain a &quot;specifier-qualifier list&quot; which in plain English is the <code>const int</code> etc stuff before the variable name. Since this isn't present, gcc for example whines about a syntax error:
<blockquote>
error: expected specifier-qualifier-list before '...' token
</blockquote>
<hr />
<blockquote>
2.What would be the purpose of such a definition (where no fields/members are defined)?
</blockquote>
I'm guessing it's either pseudo code or a dev &quot;TODO&quot; where they committed code that doesn't compile, since it has yet to be written.

entityMap|blocks|key|e2dge|text|如果这是有效的结构定义|type|unstyled|depth|inlineStyleRanges|entityRanges|data|f7ejo|4pde2|不是。|1iqhp|这样的定义(没有定义字段/成员)的目的是什么？|8up6t|4qt1d|该文件的目的是为python+CFFI解析器提供要使用的类型和函数声明。|dcgnh|此文件的目的是使用python+CFFI+ffibuilder.cdef()进行预处理。让C编译器填补空白|76eca|此外，您还可以使用“...”(字面意思就是点-点-点)在cdef()的不同位置，以便让C编译器填写细节。这些地方是：|bnart|7q30k|结构声明:任何以“...”结尾的struct+{}或联合{}，因为最后一个“field”是部分的:它可能是缺少的字段，声明顺序混乱，使用非标准对齐等。确切地说，通过查看cdef推导出的字段偏移量、总结构大小和总结构对齐不依赖于字段偏移量，而是由编译器更正。(但请注意，您只能访问您声明的字段，而不能访问其他字段。)任何不使用“...”的结构声明假设它是准确的，但这是经过检查的:如果它不正确，则会得到一个错误。|29bf1|..。|2vbjb|未知类型：....在某些情况下，您需要说明foo_t不是不透明的，而只是一个您不知道任何字段的结构；然后您将使用typedef+struct+{+...；}+foo_t;。|offset|length|style|CODE|527aq|我怀疑这对CFFI来说意味着struct+dataObject和DATA_OBJECT是不透明的类型，只能用作指针，而CFFI解析器不支持结构声明。|27pl8|据我所知，这里在clips_build.py中使用该文件来构建clipspy+python到C的接口。^0|0|0|0|0|0|0|0|0|0|0|0|1K|T|0|E|H|W|B|0|V|7^^$0|$]|1|@$2|3|4|5|6|7|8|13|9|@]|A|@]|B|$]]|$2|C|4|-4|6|7|8|14|9|@]|A|@]|B|$]]|$2|D|4|E|6|7|8|15|9|@]|A|@]|B|$]]|$2|F|4|G|6|7|8|16|9|@]|A|@]|B|$]]|$2|H|4|-4|6|7|8|17|9|@]|A|@]|B|$]]|$2|I|4|J|6|7|8|18|9|@]|A|@]|B|$]]|$2|K|4|L|6|7|8|19|9|@]|A|@]|B|$]]|$2|M|4|N|6|7|8|1A|9|@]|A|@]|B|$]]|$2|O|4|-4|6|7|8|1B|9|@]|A|@]|B|$]]|$2|P|4|Q|6|7|8|1C|9|@]|A|@]|B|$]]|$2|R|4|S|6|7|8|1D|9|@]|A|@]|B|$]]|$2|T|4|U|6|7|8|1E|9|@$V|1F|W|1G|X|Y]]|A|@]|B|$]]|$2|Z|4|10|6|7|8|1H|9|@$V|1I|W|1J|X|Y]|$V|1K|W|1L|X|Y]]|A|@]|B|$]]|$2|11|4|12|6|7|8|1M|9|@$V|1N|W|1O|X|Y]]|A|@]|B|$]]]]

<blockquote>
If this is a valid struct definition
</blockquote>
No.
<blockquote>
What would be the purpose of such a definition (where no fields/members are defined)?
</blockquote>
The file purpose is to provide the python CFFI parser with type and function declarations to use.
The purpose of this file is to preprocessed by <a href="https://cffi.readthedocs.io/en/latest/cdef.html#ffi-ffibuilder-cdef-declaring-types-and-functions" rel="nofollow noreferrer">python CFFI ffibuilder.cdef()</a>. From <a href="https://cffi.readthedocs.io/en/latest/cdef.html#letting-the-c-compiler-fill-the-gaps" rel="nofollow noreferrer">letting C compiler fill the gaps</a>:
<blockquote>
Moreover, you can use “...” (literally, dot-dot-dot) in the cdef() at various places, in order to ask the C compiler to fill in the details. These places are:
<ul>
<li>structure declarations: any struct { } or union { } that ends with “...;” as the last “field” is partial: it may be missing fields, have them declared out of order, use non-standard alignment, etc. Precisely, the field offsets, total struct size, and total struct alignment deduced by looking at the cdef are not relied upon and will instead be corrected by the compiler. (But note that you can only access fields that you declared, not others.) Any struct declaration which doesn’t use “...” is assumed to be exact, but this is checked: you get an error if it is not correct.</li>
<li>[...]</li>
<li>unknown types: [....] In some cases you need to say that foo_t is not opaque, but just a struct where you don’t know any field; then you would use <code>typedef struct { ...; } foo_t;</code>.</li>
</ul>
</blockquote>
I suspect it means to the CFFI that <code>struct dataObject</code> and <code>DATA_OBJECT</code> are opaque types meant to be used only as pointers and the CFFI parser does not support struct declarations.
The file is used <a href="https://github.com/noxdafox/clipspy/blob/90d71813aaff6ed5467b69e1b4bbdf6a82fea58e/clips/clips_build.py#L15" rel="nofollow noreferrer">here in clips_build.py</a> as I understand to build <code>clipspy</code> python interface to C.

I am reading some <a href="https://github.com/noxdafox/clipspy/blob/master/lib/clips.cdef" rel="nofollow noreferrer">code</a>, and came across this rather odd C struct definition:
<pre class="lang-c prettyprint-override"><code>typedef struct dataObject
 {
 ...;
 } DATA_OBJECT;
</code></pre>
Can anyone explain (with references if possible):
<ol>
<li>If this is a valid struct definition.</li>
<li>What would be the purpose of such a definition (where no fields/members are defined).</li>
</ol>

Clarification sought on validity and reason for "empty" C struct definition in Python CFFI definition file

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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 我正在阅读一些代码，偶然发现了这个相当奇怪的C结构定义： 有没有人能解释一下(如果可能的话，带上参考资料)： 如果这是有效的结构定义 这样的定义(没有定义字段/成员)的目的是什么？ 类型定义结构dataObject { ...；} DATA_OBJECT； [编辑] 上面的代码可以在这里找到

问要求澄清Python CFFI定义文件中“空”C结构定义的有效性和原因
EN

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问要求澄清Python CFFI定义文件中“空”C结构定义的有效性和原因EN