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No ConcurrentList in .Net 4.0?
...or all items 0-63, and a size-128 array for items 64-127. The overhead of selecting which one of two arrays to use, plus a memory barrier if desired, would be less than the overhead of even the most efficient reader-writer lock imaginable. Writes should probably use locks (lock-free would be possi...
Foreign Key to multiple tables
...ulkon I know this is an old question but the query would be something like SELECT t.Subject AS ticketSubject, CASE WHEN u.Name IS NOT NULL THEN u.Name ELSE g.Name END AS ticketOwnerName FROM Ticket t INNER JOIN Party p ON t.Owner=p.PartyId LEFT OUTER JOIN User u ON u.ID=p.PartyId LEFT OUTER JOIN Gro...
Homebrew install specific version of formula?
...installed. If you are missing the version you will still need to apply the selected answer.
– Nic Strong
Dec 19 '13 at 5:11
1
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What is the performance cost of having a virtual method in a C++ class?
..."type(-identifying) number" in the objects and using a switch statement to select the type-specific code. This avoids function call overhead completely - just doing a local jump. There is a potential cost to maintainability, recompilation dependencies etc through the forced localisation (in the sw...
Switch statement fallthrough in C#?
...# had not yet added any "soft" keywords (like 'yield', 'var', 'from', and 'select'), so they had three real options: 1) make 'fallthrough' a hard keyword (you cant use it as a variable name), 2) write code necessary to support such an soft keyword, 3) use already reserved keywords. #1 was a big issu...
Why not inherit from List?
...is the collective name given to a group of players ... Such teams could be selected to play in a match against an opposing team, to represent a football club ...". So it is my opinion that a team is a list of players (or perhaps more accurately a collection of players).
– Ben
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How to read the output from git diff?
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On my mac:
info diff then select: Output formats -> Context -> Unified format -> Detailed Unified :
Or online man diff on gnu following the same path to the same section:
File: diff.info, Node: Detailed
Unified, Next: Example Unified...
Finding a branch point with Git?
...ed from master):
or here (as viewed from topic):
in both cases, I've selected the commit that is B in my graph. Once you click on it, its full SHA is presented in a text input field just below the graph.
2. visually, but from the terminal:
git log --graph --oneline --all
(Edit/side-note:...
Coding Practices which enable the compiler/optimizer to make a faster program
...w customer\n"
"3) Destroy\n"
"4) Launch Nasal Demons\n"
"Enter selection: ";
static const size_t Menu_Text_Length = sizeof(Menu_Text) - sizeof('\0');
//...
std::cout.write(Menu_Text, Menu_Text_Length);
The efficiency of this technique can be visually demonstrated. :-)
Don't use print...
TCP 的那些事儿（上） - 更多技术 - 清泛网 - 专注C/C++及内核技术
...，这是一把双刃剑。
SACK 方法
另外一种更好的方式叫：Selective Acknowledgment (SACK)（参看RFC 2018），这种方式需要在TCP头里加一个SACK的东西，ACK还是Fast Retransmit的ACK，SACK则是汇报收到的数据碎版。参看下图：
这样，在发送端...