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When is a C++ destructor called?
...arge enough to hold 5 Foo objects.
int n = 5;
char *chunk = static_cast<char*>(::operator new(sizeof(Foo) * n));
// Use placement new to construct Foo instances at the right places in the chunk.
for(int i=0; i<n; ++i)
{
new (chunk + i*sizeof(Foo)) Foo(i);
}
...
Pass An Instantiated System.Type as a Type Parameter for a Generic Class
...y with making your generic type implement a non-generic interface, you can cast to that interface. Alternatively, you could write your own generic method which does all of the work you want to do with the generic, and call that with reflection.
– Jon Skeet
Nov ...
How do I determine which iOS SDK I have?
...), especially during betas, the best place to check which version of Xcode and related SDKs you have installed is to use "System Information".
Apple Menu > About This Mac > System Report > Software > Developer
Once there, you'll see version and build numbers for all of the major compon...
BIO与NIO、AIO的区别(这个容易理解) - 操作系统(内核) - 清泛网 - 专注C/C++及内核技术
...银行取钱，然后给你（使用异步IO时，Java将IO读写委托给OS处理，需要将数据缓冲区地址和大小传给OS(银行卡和密码)，OS需要支持异步IO操作API）；
阻塞 ： ATM排队取款，你只能等待（使用阻塞IO时，Java调用会一直阻塞到读写完...
Location Manager Error : (KCLErrorDomain error 0)
...
I still had to "Reset Content and Settings" to get the delegate to call didUpdate instead of didFail after setting a default location in the scheme editor. Then it worked fine.
– owenfi
Sep 9 '15 at 21:26
...
Cross-platform way of getting temp directory in Python
... be the tempfile module.
It has functions to get the temporary directory, and also has some shortcuts to create temporary files and directories in it, either named or unnamed.
Example:
import tempfile
print tempfile.gettempdir() # prints the current temporary directory
f = tempfile.TemporaryFil...
How do I check if a type is a subtype OR the type of an object?
...lue);
if (testInstance==null)
throw new InvalidCastException("HelperType must be derived from A");
_helperType = value;
}
}
}
I feel like I might be a bit naive here so any feedback would be welcome.
...
Java Interfaces/Implementation naming convention [duplicate]
...Truck.
When you are using the Interface in place of a sub-class you just cast it to Truck. As in List<Truck>. Putting I in front is just Hungarian style notation tautology that adds nothing but more stuff to type to your code.
All modern Java IDE's mark Interfaces and Implementations and ...
How to do a non-greedy match in grep?
I want to grep the shortest match and the pattern should be something like:
7 Answers
...
When should I use double instead of decimal?
...ecimal is causing bottlenecks or slow-downs. In those cases, I will "down cast" to double or float, but only do it internally, and carefully try to manage precision loss by limiting the number of significant digits in the mathematical operation being performed.
In general, if your value is transie...