blocks|key|1135827|text|这就是状态和复合语句之间的区别。例如，在C中，您可能会执行以下操作|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1135828|for(i=0;+i<10;+i%2B%2B)+printf("something");|code-block|syntax|javascript|1135829|或|1135830|for(i=0;+i<10;+i%2B%2B)+{printf("something");}|1135831|for循环只执行一条语句。但是，当在大括号中包含多个语句时，例如，|1135832|for(i=0;+i<10;+i%2B%2B)+{printf("something");+printf("something+else");}|1135833|然后，花括号内的整个东西就像一个语句一样。|1135834|Python也一样..。|1135835|if+x+==+y:+
++++print+'abcd'+++#+These+two+statements+are+treated+as+1+block
++++break++++++++++#+of+statements+|1135836|如果你只有一条语句，你就不需要定义一个块。|1135837|entityMap^0|K|1|0|0|0|0|0|3|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|12|8|@$9|13|A|14|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|15|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|16|8|@]|D|@]|E|$]]|$1|M|3|N|5|H|7|17|8|@]|D|@]|E|$I|J]]|$1|O|3|P|5|6|7|18|8|@$9|19|A|1A|B|C]]|D|@]|E|$]]|$1|Q|3|R|5|H|7|1B|8|@]|D|@]|E|$I|J]]|$1|S|3|T|5|6|7|1C|8|@]|D|@]|E|$]]|$1|U|3|V|5|6|7|1D|8|@]|D|@]|E|$]]|$1|W|3|X|5|H|7|1E|8|@]|D|@]|E|$I|J]]|$1|Y|3|Z|5|6|7|1F|8|@]|D|@]|E|$]]|$1|10|3|-4|5|6|7|1G|8|@]|D|@]|E|$]]]|11|$]]

Thats the difference between a statemment and a compound statement. For example, in <code>C</code> you might do something like 

<pre><code>for(i=0; i&lt;10; i++) printf("something");
</code></pre>

or 

<pre><code>for(i=0; i&lt;10; i++) {printf("something");}
</code></pre>

The <code>for</code> loop just executes a statement. However, when you include more than one statements within curly braces, like for example,

<pre><code>for(i=0; i&lt;10; i++) {printf("something"); printf("something else");}
</code></pre>

Then the entire thing within the curly braces is treated like one statement. 

Its the same with Python ...

<pre><code>if x == y: 
 print 'abcd' # These two statements are treated as 1 block
 break # of statements 
</code></pre>

If you just had one statement, you wouldnt need to define a block.

blocks|key|1135905|text|在Python中，如果块仅由一条语句组成，则始终可以用一行替换预期的块。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1135906|例如。|1135907|def+f(x):+return+x

def+f(x):
++++return+x|code-block|syntax|javascript|1135908|是等价物。Python中的任何其他块期望语法也是如此：|1135909|如果，否则，elif，for，while，def，class+.|unordered-list-item|1135910|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|P|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|Q|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|R|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|S|8|@]|9|@]|A|$]]|$1|K|3|L|5|M|7|T|8|@]|9|@]|A|$]]|$1|N|3|-4|5|6|7|U|8|@]|9|@]|A|$]]]|O|$]]

In Python you can always replace an intended block with a single line if the block consists only of a single statement.

E.g.

<pre><code>def f(x): return x

def f(x):
 return x
</code></pre>

are equivalent. The same is true for any other block-expecting syntax in Python:

<ul>
<li>if, else, elif, for, while, def, class, ...</li>
</ul>

blocks|key|1022464|text|这里不需要缩进，因为您的simple_stmt，break，在if的suite中。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1022465|...
if_stmt++++++::=++"if"+expression+":"+suite
+++++++++++++++++("elif"+expression+":"+suite)*
+++++++++++++++++["else"+":"+suite]
...
suite+++++++++::=++stmt_list+NEWLINE+%7C+NEWLINE+INDENT+statement%2B+DEDENT
statement+++++::=++stmt_list+NEWLINE+%7C+compound_stmt
...
stmt_list+++++::=++simple_stmt+(";"+simple_stmt)*+[";"]
...|code-block|syntax|javascript|1022466|在这种情况下，不需要缩进。|1022467|您只能使用简单陈述+(如return或break+)才能做到这一点，但您不可能在没有缩进的情况下拥有复合语句、if+(如while+)。|1022468|entityMap|0|LINK|mutability|MUTABLE|url|https://docs.python.org/2/reference/simple_stmts.html|1|https://docs.python.org/2/reference/compound_stmts.html#the-if-statement|2|https://docs.python.org/2/reference/compound_stmts.html#grammar-token-suite|3|4|https://docs.python.org/2/reference/compound_stmts.html#grammar-token-compound_stmt^0|C|B|O|5|V|2|Y|5|C|B|0|V|2|1|Y|5|2|0|0|0|C|6|J|5|1J|2|1O|5|5|4|3|1E|4|4|0^^$0|@$1|2|3|4|5|6|7|13|8|@$9|14|A|15|B|C]|$9|16|A|17|B|C]|$9|18|A|19|B|C]|$9|1A|A|1B|B|C]]|D|@$9|1C|A|1D|1|1E]|$9|1F|A|1G|1|1H]|$9|1I|A|1J|1|1K]]|E|$]]|$1|F|3|G|5|H|7|1L|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|1M|8|@]|D|@]|E|$]]|$1|M|3|N|5|6|7|1N|8|@$9|1O|A|1P|B|C]|$9|1Q|A|1R|B|C]|$9|1S|A|1T|B|C]|$9|1U|A|1V|B|C]]|D|@$9|1W|A|1X|1|1Y]|$9|1Z|A|20|1|21]]|E|$]]|$1|O|3|-4|5|6|7|22|8|@]|D|@]|E|$]]]|P|$Q|$5|R|S|T|E|$U|V]]|W|$5|R|S|T|E|$U|X]]|Y|$5|R|S|T|E|$U|Z]]|10|$5|R|S|T|E|$U|V]]|11|$5|R|S|T|E|$U|12]]]]

Indentation here is not required because your have <a href="https://docs.python.org/2/reference/simple_stmts.html" rel="nofollow"><code>simple_stmt</code></a>, <code>break</code>, in the <a href="https://docs.python.org/2/reference/compound_stmts.html#the-if-statement" rel="nofollow"><code>if</code></a>'s <a href="https://docs.python.org/2/reference/compound_stmts.html#grammar-token-suite" rel="nofollow"><code>suite</code></a>:

<pre><code>...
if_stmt ::= "if" expression ":" suite
 ("elif" expression ":" suite)*
 ["else" ":" suite]
...
suite ::= stmt_list NEWLINE | NEWLINE INDENT statement+ DEDENT
statement ::= stmt_list NEWLINE | compound_stmt
...
stmt_list ::= simple_stmt (";" simple_stmt)* [";"]
...
</code></pre>

In this case indentation is not required.

You can do this only with <a href="https://docs.python.org/2/reference/simple_stmts.html" rel="nofollow">simple statements</a>,like <code>return</code> or <code>break</code>, but you can't have a <a href="https://docs.python.org/2/reference/compound_stmts.html#grammar-token-compound_stmt" rel="nofollow">compound statements</a>, <code>if</code> like <code>while</code>, without indentation .

I came across a piece of code (simplified for the question) structured like so:

<pre><code>while True:
 if x == y: break
</code></pre>

My understanding of Python thus far is that the interpreter is highly dependent on tabs/spaces to understand the contents of things like loops and conditionals, but the above code style runs without issue, suggesting this isn't quite true. 

Can someone explain the nuance?

Indentation in Python not always necessary?

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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我遇到了一段代码(简化了这个问题)，结构如下：while True:    if x == y: break到目前为止，我对Python的理解是，解释器高度依赖于制表符/空格来理解循环和条件等内容，但是上面的代码风格运行时没有问题，这表明这并不完全正确。有人能解释一下细微差别吗？

问Python中的缩进并不总是必要的？
EN

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问Python中的缩进并不总是必要的？EN