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How can I use pointers in Java?
...Java doesn't have pointers, but I heard that Java programs can be created with pointers and that this can be done by the few who are experts in java. Is it true?
...
How can I make a div stick to the top of the screen once it's been scrolled to?
I would like to create a div, that is situated beneath a block of content but that once the page has been scrolled enough to contact its top boundary, becomes fixed in place and scrolls with the page.
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What is “vectorization”?
..., fortran ... some other ... but I've never found an explanation what does it mean, and what it does? So I'm asking here, what is vectorization, and what does it mean for example, that "a loop is vectorized" ?
...
How can I check if an element exists in the visible DOM?
How do you test an element for existence without the use of the getElementById method?
25 Answers
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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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How is __eq__ handled in Python and in what order?
Since Python does not provide left/right versions of its comparison operators, how does it decide which function to call?
3...
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 ...
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...