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Why are hexadecimal numbers prefixed with 0x?
...
Short story: The 0 tells the parser it's dealing with a constant (and not an identifier/reserved word). Something is still needed to specify the number base: the x is an arbitrary choice.
Long story: In the 60's, the prevalent programming number systems were d...
How do I find the length of an array?
...f(a)/sizeof(*a)) << std::endl;
This doesn't work on pointers (i.e. it won't work for either of the following):
int *p = new int[7];
std::cout << "Length of array = " << (sizeof(p)/sizeof(*p)) << std::endl;
or:
void func(int *p)
{
std::cout << "Length of array ...
How to check if a process id (PID) exists
...ess, use
kill -0 $pid
But just as @unwind said, if you're going to kill it anyway, just
kill $pid
or you will have a race condition.
If you want to ignore the text output of kill and do something based on the exit code, you can
if ! kill $pid > /dev/null 2>&1; then
echo "Could ...
Warn user before leaving web page with unsaved changes
I have some pages with forms in my application.
18 Answers
18
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Warning: “format not a string literal and no format arguments”
...think NSLog() likes taking only one argument, which is what you're passing it. Also, it already does the formatting for you. Why not just do this?
NSLog(@"%@ %@, %@",
errorMsgFormat,
error,
[error userInfo]);
Or, since you say errorMsgFormat is a format string with a sin...
android studio 0.4.2: Gradle project sync failed error
...error when opening a project:
'Gradle project sync failed. Basic functionality (e.g. editing, debugging) will not work proprerly'
...
How to automatically install Emacs packages by specifying a list of package names?
...ackages you want
(setq package-list '(package1 package2))
; list the repositories containing them
(setq package-archives '(("elpa" . "http://tromey.com/elpa/")
("gnu" . "http://elpa.gnu.org/packages/")
("marmalade" . "http://marmalade-repo.org/packa...
Execute the setInterval function without delay the first time
It's there a way to configure the setInterval method of javascript to execute the method immediately and then executes with the timer
...
Accessing constructor of an anonymous class
...I have a concrete class Class1 and I am creating an anonymous class out of it.
10 Answers
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What is a practical use for a closure in JavaScript?
...tion();
}
}
})();
As you can see there, a is now an object, with a method publicfunction ( a.publicfunction() ) which calls privatefunction, which only exists inside the closure. You can NOT call privatefunction directly (i.e. a.privatefunction() ), just publicfunction().
Its a minim...