blocks|key|1189701|text|checker+=+None+

if+some_decision:
++++checker+=+True

if+checker:
++++#+some+stuff|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1189702|编辑|unstyled|1189703|欲了解更多信息，请访问：http://docs.python.org/library/functions.html#bool|offset|length|1189704|您的代码也可以工作，因为在必要时会将1转换为True。实际上，Python很长一段时间都没有布尔类型(就像在旧的C中一样)，一些程序员仍然使用整数而不是布尔值。|style|CODE|1189705|entityMap|0|LINK|mutability|MUTABLE|url|http://docs.python.org/library/functions.html#bool^0|0|0|C|1E|0|0|I|1|M|4|0^^$0|@$1|2|3|4|5|6|7|W|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|X|8|@]|9|@]|A|$]]|$1|G|3|H|5|F|7|Y|8|@]|9|@$I|Z|J|10|1|11]]|A|$]]|$1|K|3|L|5|F|7|12|8|@$I|13|J|14|M|N]|$I|15|J|16|M|N]]|9|@]|A|$]]|$1|O|3|-4|5|F|7|17|8|@]|9|@]|A|$]]]|P|$Q|$5|R|S|T|A|$U|V]]]]

<pre><code>checker = None 

if some_decision:
 checker = True

if checker:
 # some stuff
</code></pre>

[Edit]

For more information: <a href="http://docs.python.org/library/functions.html#bool" rel="noreferrer">http://docs.python.org/library/functions.html#bool</a>

Your code works too, since <code>1</code> is converted to <code>True</code> when necessary.
Actually Python didn't have a boolean type for a long time (as in old C), and some programmers still use integers instead of booleans.

blocks|key|1189791|text|布尔型内建函数大写：True和False。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1189792|还请注意，您可以将checker+=+bool(some_decision)作为一种简写--+bool将只返回True或False。|1189793|为了便于将来参考，根据这些函数的结果，classes+defining+__nonzero__+or+__len__将是True或False，但实际上所有其他对象的布尔结果都是True+(除了None对象、空序列和数字零)。|1189794|entityMap|0|LINK|mutability|MUTABLE|url|http://docs.python.org/library/functions.html#bool|1|http://docs.python.org/library/stdtypes.html#truth-value-testing^0|A|4|F|5|0|9|T|1B|4|1J|4|1O|5|1B|4|0|0|10|B|1F|7|1O|4|1T|5|2G|4|2O|4|J|13|1|0^^$0|@$1|2|3|4|5|6|7|T|8|@$9|U|A|V|B|C]|$9|W|A|X|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|Y|8|@$9|Z|A|10|B|C]|$9|11|A|12|B|C]|$9|13|A|14|B|C]|$9|15|A|16|B|C]]|D|@$9|17|A|18|1|19]]|E|$]]|$1|H|3|I|5|6|7|1A|8|@$9|1B|A|1C|B|C]|$9|1D|A|1E|B|C]|$9|1F|A|1G|B|C]|$9|1H|A|1I|B|C]|$9|1J|A|1K|B|C]|$9|1L|A|1M|B|C]]|D|@$9|1N|A|1O|1|1P]]|E|$]]|$1|J|3|-4|5|6|7|1Q|8|@]|D|@]|E|$]]]|K|$L|$5|M|N|O|E|$P|Q]]|R|$5|M|N|O|E|$P|S]]]]

The boolean builtins are capitalized: <code>True</code> and <code>False</code>.

Note also that you can do <code>checker = bool(some_decision)</code> as a bit of shorthand -- <a href="http://docs.python.org/library/functions.html#bool" rel="noreferrer"><code>bool</code></a> will only ever return <code>True</code> or <code>False</code>.

It's good to know for future reference that <a href="http://docs.python.org/library/stdtypes.html#truth-value-testing" rel="noreferrer">classes defining <code>__nonzero__</code> or <code>__len__</code></a> will be <code>True</code> or <code>False</code> depending on the result of those functions, but virtually every other object's boolean result will be <code>True</code> (except for the <code>None</code> object, empty sequences, and numeric zeros).

blocks|key|1405133|text|True+...显然还有False。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1405134|否则，None的计算结果为False，整数0和浮点型0.0也是如此(尽管我不会使用这样的浮点型)。此外，空列表[]、空元组()和空字符串''或""的计算结果为False。|1405135|使用函数bool()自己尝试一下|1405136|bool([])
bool(['a+value'])
bool('')
bool('A+string')
bool(True)++#+;-)
bool(False)
bool(0)
bool(None)
bool(0.0)
bool(1)|code-block|syntax|javascript|1405137|等等。|1405138|entityMap^0|0|4|C|5|0|3|4|L|1|Q|3|1J|2|1P|2|1W|2|1Z|2|0|4|6|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@$9|T|A|U|B|C]|$9|V|A|W|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|X|8|@$9|Y|A|Z|B|C]|$9|10|A|11|B|C]|$9|12|A|13|B|C]|$9|14|A|15|B|C]|$9|16|A|17|B|C]|$9|18|A|19|B|C]|$9|1A|A|1B|B|C]]|D|@]|E|$]]|$1|H|3|I|5|6|7|1C|8|@$9|1D|A|1E|B|C]]|D|@]|E|$]]|$1|J|3|K|5|L|7|1F|8|@]|D|@]|E|$M|N]]|$1|O|3|P|5|6|7|1G|8|@]|D|@]|E|$]]|$1|Q|3|-4|5|6|7|1H|8|@]|D|@]|E|$]]]|R|$]]

<code>True</code> ... and <code>False</code> obviously.

Otherwise, <code>None</code> evaluates to False, as does the integer <code>0</code> and also the float <code>0.0</code> (although I wouldn't use floats like that).
Also, empty lists <code>[]</code>, empty tuplets <code>()</code>, and empty strings <code>''</code> or <code>""</code> evaluate to False.

Try it yourself with the function <code>bool()</code>:

<pre><code>bool([])
bool(['a value'])
bool('')
bool('A string')
bool(True) # ;-)
bool(False)
bool(0)
bool(None)
bool(0.0)
bool(1)
</code></pre>

etc..

blocks|key|1405200|text|与声明boolean+flag+=+True的Java语言不同，在Python语言中只需声明myFlag+=+True|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1405201|Python会将其解释为布尔变量|1405202|entityMap^0|3|J|1A|D|0|0^^$0|@$1|2|3|4|5|6|7|J|8|@$9|K|A|L|B|C]|$9|M|A|N|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|O|8|@]|D|@]|E|$]]|$1|H|3|-4|5|6|7|P|8|@]|D|@]|E|$]]]|I|$]]

Unlike Java where you would declare <code>boolean flag = True</code>, in Python you can just declare <code>myFlag = True</code>

Python would interpret this as a boolean variable

Does Python actually contain a Boolean value? I know that you can do:

<pre><code>checker = 1
if checker:
 #dostuff
</code></pre>

But I'm quite pedantic and enjoy seeing booleans in Java. For instance:

<pre><code>Boolean checker;
if (someDecision)
{
 checker = true;
}
if(checker)
{
 //some stuff
}
</code></pre>

Is there such a thing as a Boolean in Python? I can't seem to find anything like it in the documentation.

How do I use a Boolean in Python?

Python

Java

Python真的包含布尔值吗？我知道你可以这样做：checker = 1if checker:    #dostuff但我很学究，喜欢看到Java中的布尔值。例如：Boolean checker;if (someDecision){    checker = true;}if(checker){    //some s...

问如何在Python中使用布尔值？
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