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Why doesn't c++ have &&= or ||= for booleans?
Is there a "very bad thing" that can happen &&= and ||= were used as syntactic sugar for bool foo = foo && bar and bool foo = foo || bar ?
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Return type of '?:' (ternary conditional operator)
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Expressions don't have return types, they have a type and - as it's known in the latest C++ standard - a value category.
A conditional expression can be an lvalue or an rvalue. This is its value category. (This is somewhat of a simplification, in C++11 we have lvalues, xvalues a...
querySelector and querySelectorAll vs getElementsByClassName and getElementById in JavaScript
... would like to know what exactly is the difference between querySelector and querySelectorAll against getElementsByClassName and getElementById ?
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How to convert a String to its equivalent LINQ Expression Tree?
...o you mean by "writing a parser (using Expression under the hood)" Parsing and then generating an expression tree, or does System.Linq.Expressions have some parsing mechanism?
– AK_
Jul 1 '13 at 14:51
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How do you use “
I just finished reading about scoping in the R intro , and am very curious about the <<- assignment.
6 Answers
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nginx missing sites-available directory
I installed Nginx on Centos 6 and I am trying to set up virtual hosts. The problem I am having is that I can't seem to find the /etc/nginx/sites-available directory.
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How to get the process ID to kill a nohup process?
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When using nohup and you put the task in the background, the background operator (&) will give you the PID at the command prompt. If your plan is to manually manage the process, you can save that PID and use it later to kill the process i...
How to check iOS version?
...lable(iOS 9, *) {}
In Objective-C, you need to check the system version and perform a comparison.
[[NSProcessInfo processInfo] operatingSystemVersion] in iOS 8 and above.
As of Xcode 9:
if (@available(iOS 9, *)) {}
The full answer …
In Objective-C, and Swift in rare cases, it's better to...
How to run a Runnable thread in Android at defined intervals?
... developed an application to display some text at defined intervals in the Android emulator screen. I am using the Handler class. Here is a snippet from my code:
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What are dictionary view objects?
...sentially what their name says: views are simply like a window on the keys and values (or items) of a dictionary. Here is an excerpt from the official documentation for Python 3:
>>> dishes = {'eggs': 2, 'sausage': 1, 'bacon': 1, 'spam': 500}
>>> keys = dishes.keys()
>>>...