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How to check if object has any properties in JavaScript?
...d Apr 20 '10 at 6:49
Daniel VassalloDaniel Vassallo
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How do you remove duplicates from a list whilst preserving order?
...n seen or seen_add(x))]
Why assign seen.add to seen_add instead of just calling seen.add? Python is a dynamic language, and resolving seen.add each iteration is more costly than resolving a local variable. seen.add could have changed between iterations, and the runtime isn't smart enough to rule t...
INNER JOIN vs LEFT JOIN performance in SQL Server
... slower; by definition, an outer join (LEFT JOIN or RIGHT JOIN) has to do all the work of an INNER JOIN plus the extra work of null-extending the results. It would also be expected to return more rows, further increasing the total execution time simply due to the larger size of the result set.
(A...
How to check if a Unix .tar.gz file is a valid file without uncompressing?
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What about just getting a listing of the tarball and throw away the output, rather than decompressing the file?
tar -tzf my_tar.tar.gz >/dev/null
Edited as per comment. Thanks zrajm!
Edit as per comment. Thanks Frozen Flame! This test in no way implies integrity ...
WaitAll vs WhenAll
What is the difference between Task.WaitAll() and Task.WhenAll() from the Async CTP ?
Can you provide some sample code to illustrate the different use cases ?
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Using backticks around field names
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To me it makes a lot of sense to use them at all times when dealing with field names.
Firstly, once you get into the habit, it doesn't hurt to just hit the backtick key.
Secondly, to me, it makes it easier to see what exactly are the fields in your query, and what ar...
Is cout synchronized/thread-safe?
...f particular interest here is the fact that cout is buffered. Even if the calls to write (or whatever it is that accomplishes that effect in that particular implementation) are guaranteed to be mutually exclusive, the buffer might be shared by the different threads. This will quickly lead to corrupt...
VS2012 关闭浏览信息（提高编译速度）的方法 - C/C++ - 清泛网 - 专注C/C++及内核技术
VS2012 关闭浏览信息（提高编译速度）的方法vs2012关闭浏览信息（不生成.bsc文件，可显著提升编译速度）的方法如下（工程属性 -> C C++ -> 浏览信息 -> 启用浏览信息：否）vs2012关闭浏览信息（不生成.bsc文件，可显著提升编译速度...
VS编译dll时报编译错误：fatal error LNK1561: entry point must be define...
VS编译dll时报编译错误：fatal error LNK1561: entry point must be definedentry-point-must-be-definedVS编译dll时报编译错误：fatal error LNK1561: entry point must be defined1、可能是连接命令中的 subsystem不正确，在Project Properties->Linker->System中设置，改为 V...
Socket.IO Authentication
I am trying to use Socket.IO in Node.js, and am trying to allow the server to give an identity to each of the Socket.IO clients. As the socket code is outside the scope of the http server code, it doesn't have easy access to the request information sent, so I'm assuming it will need to be sent up d...