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What is the instanceof operator in JavaScript?
... type.
Here are some good examples and here is an example taken directly from Mozilla's developer site:
var color1 = new String("green");
color1 instanceof String; // returns true
var color2 = "coral"; //no type specified
color2 instanceof String; // returns false (color2 is not a String object)
...
How can I get the current page name in WordPress?
...atic page is set as the front page, $pagename will not be set. Retrieve it from the queried object
$post = $wp_query->get_queried_object();
$pagename = $post->post_name;
}
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How to format a number as percentage in R?
..., 0, 0.1, 0.555555, 1, 100)
percent(x)
(If you prefer, change the format from "f" to "g".)
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Bash script to receive and repass quoted parameters
... "$@" works with any Bourne shell or Bourne shell derivative (from 1978 onwards), including Korn and Bash. Probably 95% of the time, using "$@" is correct and $* is wrong.
– Jonathan Leffler
Jan 16 '09 at 8:03
...
When would you use a WeakHashMap or a WeakReference?
...ork on.
Naturally you want to cache these
images, because loading them from disk
is very expensive and you want to
avoid the possibility of having two
copies of the (potentially gigantic)
image in memory at once.
Because an image cache is supposed to
prevent us from reloading imag...
std::wstring VS std::string
...ind of esoteric language glyphs (Klingon? Elvish?), while UTF-8 will spend from 1 to 4 bytes.
See http://en.wikipedia.org/wiki/UTF-8#Compared_to_UTF-16 for more info.
Conclusion
When I should use std::wstring over std::string?
On Linux? Almost never (§).
On Windows? Almost always (§).
On cros...
What is the difference between Cygwin and MinGW?
...ing Windows, but there are other options too. If you use such a framework from the start, you can not only reduce your headaches when it comes time to port to another platform but you can use the same graphical widgets - windows, menus and controls - across all platforms if you're writing a GUI app...
How to create a custom exception type in Java? [duplicate]
...
You need to create a class that extends from Exception. It should look like this:
public class MyOwnException extends Exception {
public MyOwnException () {
}
public MyOwnException (String message) {
super (message);
}
public MyOwnEx...
How to pretty-print a numpy.array without scientific notation and with given precision?
...689 0.754 0.624 0.901 0.049 0.582 0.557 0.348]
To prevent zeros from being stripped from the end of floats:
np.set_printoptions now has a formatter parameter which allows you to specify a format function for each type.
np.set_printoptions(formatter={'float': '{: 0.3f}'.format})
print(x)...
How do I check whether a jQuery element is in the DOM?
...s I was typing my question: Call
$foo.parent()
If $f00 has been removed from the DOM, then $foo.parent().length === 0. Otherwise, its length will be at least 1.
[Edit: This is not entirely correct, because a removed element can still have a parent; for instance, if you remove a <ul>, each...