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What does the “at” (@) symbol do in Python?
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An @ symbol at the beginning of a line is used for class, function and method decorators.
Read more here:
PEP 318: Decorators
Python Decorators
The most common Python decorators you'll run into are:
@property
@classmethod
@staticmethod
If you see an @ in the middle of a line, that's ...
How do you test that a Python function throws an exception?
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I'm using Python 2.7.10, and the above doesn't work; context.exception does not give the message; it is a type.
– LateCoder
Feb 25 '16 at 16:55
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UIImagePickerController error: Snapshotting a view that has not been rendered results in an empty sn
I am getting this error only in iOS 7 and the application crashed.
In iOS 6, I never get any error, just once of memory warning when opening the camera.
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Bootstrap Dropdown menu is not working
...n my machine. Anyone have any ideas? I have been staring at it for an hour and can't seem to figure out what the problem is.
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Extending from two classes
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You can only Extend a single class. And implement Interfaces from many sources.
Extending multiple classes is not available. The only solution I can think of is not inheriting either class but instead having an internal variable of each class and doing more o...
Determining if a number is either a multiple of ten or within a particular set of ranges
...m - 1) / 10) % 2 == 1 && num <= 100)
But that's rather dense, and you might be better off just listing the options explicitly.
Now that you've given a better idea of what you are doing, I'd write the second one as:
int getRow(int num) {
return (num - 1) / 10;
}
if (ge...
What does this mean: Failure [INSTALL_FAILED_CONTAINER_ERROR]?
I try to deploy my app and sometimes get this error:
14 Answers
14
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Representing Monetary Values in Java [closed]
I understand that BigDecimal is recommended best practice for representing monetary values in Java. What do you use? Is there a better library that you prefer to use instead?
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Can't connect Nexus 4 to adb: unauthorized
I have a Nexus 4 with Android 4.3 and I am trying to connect the device to a computer with Windows 7 64bit.
26 Answers
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Checking if a key exists in a JavaScript object?
...r, if you want to particularly test for properties of the object instance (and not inherited properties), use hasOwnProperty:
obj.hasOwnProperty("key") // true
For performance comparison between the methods that are in, hasOwnProperty and key is undefined, see this benchmark
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