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MySQL CONCAT returns NULL if any field contain NULL
...ate_name`,''),'-',COALESCE(`model`,''),'-',COALESCE(`ip`,''),'-',COALESCE(`os_type`,''),'-',COALESCE(`os_version`,'')) AS device_name
FROM devices
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How do I make python wait for a pressed key?
... the user to press enter though.
One might want to use msvcrt ((Windows/DOS only) The msvcrt module gives you access to a number of functions in the Microsoft Visual C/C++ Runtime Library (MSVCRT)):
import msvcrt as m
def wait():
m.getch()
This should wait for a key press.
Additional info:...
How can I get the concatenation of two lists in Python without modifying either one? [duplicate]
...;>> sum([(1,2), (1,), ()], ())
(1, 2, 1)
>>> sum([Counter('123'), Counter('234'), Counter('345')], Counter())
Counter({'1':1, '2':2, '3':3, '4':2, '5':1})
>>> sum([True, True, False], False)
2
With the notable exception of strings:
>>> sum(['123', '345', '567'],...
Good examples of Not a Functor/Functor/Applicative/Monad?
...fied. For example, fmap id ≠ id, because let (Q(f,_)) = fmap id (Q(read,"123")) in f "456" is 123, but let (Q(f,_)) = id (Q(read,"123")) in f "456" is 456.
In fact, F is only a profunctor, - it is neither a functor nor a contrafunctor.
A lawful functor that is not applicative because the type s...
Launch an app on OS X with command line
I want to launch an app on OSX from a script. I need pass it command line arguments. Unfortunately, open doesn't accept command line args.
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GDB missing in OS X v10.9 (Mavericks)
I went to use GDB in OS X v10.9 (Mavericks), and it's not there. Where has it gone?
12 Answers
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How to copy a selection to the OS X clipboard
I have an area selected in Vim. How can I copy it into the OS X clipboard?
27 Answers
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how to clear the screen in python [duplicate]
....
I use both Windows and Linux and I use commands to clear the screen in those, but I don't know how to do it in Python.
1 ...
error C2662: “Screen::move”: 不能将“this”指针从“const Screen”转...
...ursor = row + c;
return *this;
}
const Screen& Screen::display(std::ostream& os) const
{
os << contents << '\n';
return *this;
}
//main中处理
myScreen.display(cout).move(4,0).set('#').display(cout);
解决办法：通过返回调用函数的对象的引用，可以将一些...
Mac OS X Git安装教程 - 更多技术 - 清泛网 - 专注C/C++及内核技术
Mac OS X Git安装教程下载：http: code.google.com p git-osx-installer 下载最新的PGK文件。图形化OpeninGitGui：http: code.google.com p git-osx-installer...下载：http://code.google.com/p/git-osx-installer/
下载最新的PGK文件。
图形化OpeninGitGui：
http://code.goo...