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How can I check if an element exists in the visible DOM?
...
It seems some people are landing here, and simply want to know if an element exists (a little bit different to the original question).
That's as simple as using any of the browser's selecting method, and checking it for a truthy value (generally).
For example, if my element had an...
jQuery same click event for multiple elements
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$('.class1, .class2').on('click', some_function);
Or:
$('.class1').add('.class2').on('click', some_function);
This also works with existing objects:
const $class1 = $('.class1');
const $class2 = $('.class2');
$class1.add($class2).on('click', some_fu...
How to initialize array to 0 in C?
...4);
That would be useful if you had changed it and wanted to reset it back to all zeros.
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Passing an array as a function parameter in JavaScript
I'd like to call a function using an array as parameters:
10 Answers
10
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Resetting generator object in Python
...reate a second version of your generator:
y = FunctionWithYield()
y, y_backup = tee(y)
for x in y:
print(x)
for x in y_backup:
print(x)
This could be beneficial from memory usage point of view if the original iteration might not process all the items.
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Difference between ref and out parameters in .NET [duplicate]
... as a ref parameter it has to be set to something.
int x;
Foo(out x); // OK
int y;
Foo(ref y); // Error: y should be initialized before calling the method
Ref parameters are for data that might be modified, out parameters are for data that's an additional output for the function (eg int.TryParse...
How to convert java.util.Date to java.sql.Date?
...ut a time of day and without a time zone.
Details
If you are trying to work with date-only values (no time-of-day, no time zone), use the LocalDate class rather than java.util.Date.
java.time
In Java 8 and later, the troublesome old date-time classes bundled with early versions of Java have been s...
Global and local variables in R
...ives the following error: Error: object 'bar' not found.
If you want to make bar a global variable, you should do:
foo <- function() {
bar <<- 1
}
foo()
bar
In this case bar is accessible from outside the function.
However, unlike C, C++ or many other languages, brackets do not det...
How do I clone a single branch in Git?
I have a local Git repository called 'skeleton' that I use for storing project skeletons. It has a few branches, for different kinds of projects:
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Usage of __slots__?
...g value references in slots instead of __dict__.
Denying __dict__ and __weakref__ creation if parent classes deny them and you declare __slots__.
Quick Caveats
Small caveat, you should only declare a particular slot one time in an inheritance tree. For example:
class Base:
__slots__ = 'foo', 'b...