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What is the difference between null and undefined in JavaScript?
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alert(typeof TestVar); //shows undefined
null is an assignment value. It can be assigned to a variable as a representation of no value:
var TestVar = null;
alert(TestVar); //shows null
alert(typeof TestVar); //shows object
From the preceding examples, it is clear that undefined and null are ...
How does Apple find dates, times and addresses in emails?
... email contains a date, time or location, the text becomes a hyperlink and it is possible to create an appointment or look at a map simply by tapping the link. It not only works for emails in English, but in other languages also. I love this feature and would like to understand how they do it.
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Adding hours to JavaScript Date object?
It amazes me that JavaScript's Date object does not implement an add function of any kind.
14 Answers
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HTML5 best practices; section/header/aside/article elements
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Actually, you are quite right when it comes to header/footer. Here is some basic information on how each of the major HTML5 tags can/should be used (I suggest reading the full source linked at the bottom):
section – Used for grouping tog...
What was the strangest coding standard rule that you were forced to follow? [closed]
When I asked this question I got almost always a definite yes you should have coding standards.
112 Answers
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What is the difference between pip and conda?
...ager for python packages. However, I saw the installation on IPython's website use conda to install IPython.
12 Answers
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UIButton inside a view that has a UITapGestureRecognizer
I have view with a UITapGestureRecognizer . So when I tap on the view another view appears above this view. This new view has three buttons. When I now press on one of these buttons I don't get the buttons action, I only get the tap gesture action. So I'm not able to use these buttons anymore. What...
Android error: Failed to install *.apk on device *: timeout
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Try changing the ADB connection timeout. I think it defaults that to 5000ms and I changed mine to 10000ms to get rid of that problem.
If you are in Eclipse, you can do this by going through
Window -> Preferences -> Android -> DDMS -> ADB Connection Timeout (ms...
“unrecognized selector sent to instance” error in Objective-C
I created a button and added an action for it, but as soon as it invoked, I got this error:
38 Answers
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How to hide soft keyboard on android after clicking outside EditText?
...ippet simply hides the keyboard:
public static void hideSoftKeyboard(Activity activity) {
InputMethodManager inputMethodManager =
(InputMethodManager) activity.getSystemService(
Activity.INPUT_METHOD_SERVICE);
inputMethodManager.hideSoftInputFromWindow(
activity...