问一下 ()?'':'' 的写法！

我以前见到过，现在想不起来了！
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a = 0
b = (0 == a) ? 1 : 0

--
CopyLeft (^_^) Scorpio Auding
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谢谢，你这不对！

我找到了

(cond) and (expr_true) or (expr_false)


2005/11/9, Scorpio Auding <auding at gmail.com>:
>
> a = 0
> b = (0 == a) ? 1 : 0
>
> --
> CopyLeft (^_^) Scorpio Auding
> _______________________________________________
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def ifelse(cond, expr_true, expr_false):
return (cond and [expr_true] or [expr_false])[0]

(cond) and (expr_true) or (expr_false)， expr_true如果是Python认为是 
False的值时，会得到错误的结果。而[expr_true]永远不会为False.

Guofeng Yuan 写道:

> 谢谢，你这不对！
>
> 我找到了
>
> (cond) and (expr_true) or (expr_false)
>
>
> 2005/11/9, Scorpio Auding <auding at gmail.com auding at gmail.com>>:
>
>     a = 0
>     b = (0 == a) ? 1 : 0
>
>     -- 
>     CopyLeft (^_^) Scorpio Auding
>     _______________________________________________
>     Python中文技术讨论邮件列表
>     发言: 发邮件到 python-chinese at lists.python.cn
>     python-chinese at lists.python.cn>
>     订阅: 发送 subscribe 到 python-chinese-request at lists.python.cn
>     python-chinese-request at lists.python.cn>
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>     python-chinese-request at lists.python.cn>
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>     <http://python.cn/mailman/listinfo/python-chinese>
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也可以这样写的：
[expr_true，expr_false][cond !=True]
不过后面一定要写成 cond  !=True 或 not cond 而不是只有 cond

在 2005年11月9日 星期三 10:34，Guofeng Yuan 写道：
> 谢谢，你这不对！
>
> 我找到了
>
> (cond) and (expr_true) or (expr_false)
>
> 2005/11/9, Scorpio Auding <auding at gmail.com>:
> > a = 0
> > b = (0 == a) ? 1 : 0
> >
> > --
> > CopyLeft (^_^) Scorpio Auding
> > _______________________________________________
> > Python中文技术讨论邮件列表
> > 发言: 发邮件到 python-chinese at lists.python.cn
> > 订阅: 发送 subscribe 到 python-chinese-request at lists.python.cn
> > 退订: 发送 unsubscribe 到 python-chinese-request at lists.python.cn
> > 详细说明: http://python.cn/mailman/listinfo/python-chinese