Python While 循环单行
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/15185746/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
While loop one-liner
提问by user2128561
Is it possible for to have a python while loop purely on one line, I've tried this:
是否有可能完全在一行上有一个 python while 循环，我试过这个：
while n<1000:if n%3==0 or n%5==0:rn+=n
But it produces an error message: Invalid Syntaxat the ifstatement
但它会产生一条错误消息：Invalid Syntax在if语句中
回答by Martijn Pieters
When using a compound statementin python (statements that need a suite, an indented block), and that block contains only simple statements, you can remove the newline, and separate the simple statements with semicolons.
在 python 中使用复合语句（需要套件的语句，缩进块）并且该块仅包含简单语句时，您可以删除换行符，并用分号分隔简单语句。
However, that does notsupport compound statements.
然而，这并不能支持复合语句。
So:
所以：
if expression: print "something"
works, but
有效，但是
while expression: if expression: print "something"
does notbecause both the whileand ifstatements are compound.
确实不是因为无论是while和if语句化合物。
For your specificexample, you can replace the if expression: assignmentpart with a conditional expression, so by using an expression instead of a complex statement:
对于您的特定示例，您可以if expression: assignment使用条件表达式替换该部分，因此使用表达式而不是复杂语句：
while expression: target = true_expression if test_expression else false_expression
in general, or while n<1000: rn += n if not (n % 3 and n % 5) else 0specifically.
一般而言，或while n<1000: rn += n if not (n % 3 and n % 5) else 0具体而言。
From a style perspective, you generally want to leave that one line on it's own, though.
不过，从风格的角度来看，您通常希望单独留下一行。
回答by l4mpi
In your example, you try to collapse two levels of blocks / indentation into a single line, which is not allowed. You can only do this with simple statements, not loops, if statements, function definitions etc. That said, for your example there is a workaround using the ternary operator:
在您的示例中，您尝试将两级块/缩进折叠为一行，这是不允许的。您只能使用简单的语句执行此操作，而不能使用循环、if 语句、函数定义等。也就是说，对于您的示例，有一种使用三元运算符的解决方法：
while n < 1000: rn += n if (n % 3 == 0 or n % 5 == 0) else 0
which reads as 'add n to rn if the condition holds, else add 0'.
如果条件成立，则读取为“将 n 添加到 rn，否则添加 0”。
回答by JHolta
It is posible to do something similar:
可以做类似的事情：
rn = 100
for n in range(10): rn += n if (n%3==0 or n%5==0) else 0
