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What is the difference between a weak reference and an unowned reference?
... provide this benefit).
A weak reference allows the possibility of it to become nil (this happens automatically when the referenced object is deallocated), therefore the type of your property must be optional - so you, as a programmer, are obligated to check it before you use it (basically the compi...
Why is Go so slow (compared to Java)?
As we could see from The Computer Language Benchmarks Game in 2010:
10 Answers
10
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高并发服务端分布式系统设计概要 - C/C++ - 清泛网 - 专注C/C++及内核技术
...服务端分布式系统设计概要张峻崇 原创主页：http: ccixx.com 昵称：Jone Zhang我们今天要设计的系统目标很明确，针对千万级以上PV的网站，设计一套用于后台的高...张峻崇 原创 主页：http://ccixx.com 昵称：Jone Zhang
我们今天要设...
What are the undocumented features and limitations of the Windows FINDSTR command?
The Windows FINDSTR command is horribly documented. There is very basic command line help available through FINDSTR /? , or HELP FINDSTR , but it is woefully inadequate. There is a wee bit more documentation online at https://docs.microsoft.com/en-us/windows-server/administration/windows-commands...
What happens to a declared, uninitialized variable in C? Does it have a value?
...in undefined behavior.
void foo() {
int x;
printf("%d", x); // the compiler is free to crash here
}
In practice, they tend to just have some nonsensical value in there initially - some compilers may even put in specific, fixed values to make it obvious when looking in a debugger - but stric...
How can HTML5 “replace” Flash? [closed]
...hat people loosely refer to HTML5 in the context of this discussion is the combination of HTML as a markup language, CSS which specifies how it is rendered, and the javascript code which manipulates the HTML and CSS dynamically.
Furthermore, HTML5 not only has the standard text elements, but also &...
Why is React's concept of Virtual DOM said to be more performant than dirty model checking?
... Using a virtual DOM to generate a real DOM patch
In React, each of your components have a state. This state is like an observable you might find in knockout or other MVVM style libraries. Essentially, React knows when to re-render the scene because it is able to observe when this data changes. Di...
Insert, on duplicate update in PostgreSQL?
... edited May 23 '17 at 11:54
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answered Jul 10 '09 at 12:18
Stephen DenneStephe...
phpunit mock method multiple calls with different arguments
... edited May 23 '17 at 11:55
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111 silver badge
answered May 13 '11 at 8:14
edorianedorian
...
What causes and what are the differences between NoClassDefFoundError and ClassNotFoundException?
...ed-for class definition
existed when the currently executing
class was compiled, but the definition
can no longer be found.
So, it appears that the NoClassDefFoundError occurs when the source was successfully compiled, but at runtime, the required class files were not found. This may be some...