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How to “test” NoneType in python?
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It can also be done with isinstance as per Alex Hall's answer :
>>> NoneType = type(None)
>>> x = None
>>> type(x) == NoneType
True
>>> isinstance(x, NoneType)
True
isinstance is also intuitive but there is the complication that it re...
Can CSS detect the number of children an element has?
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No. Well, not really. There are a couple of selectors that can get you somewhat close, but probably won't work in your example and don't have the best browser compatibility.
:only-child
The :only-child is one of the few true counting sele...
“Incorrect string value” when trying to insert UTF-8 into MySQL via JDBC?
...ter you can change the column encoding from utf8 to utf8mb4. This encoding allows storage of characters that occupy 4 bytes in UTF-8.
You may also have to set the server property character_set_server to utf8mb4 in the MySQL configuration file. It seems that Connector/J defaults to 3-byte Unicode ot...
Converting a String to DateTime
...Time(format: "ddMMyyyy"); // {29.02.1996 00:00:00}
mydate = "2016 3";
date = mydate.ToDateTime("yyyy M"); // {01.03.2016 00:00:00}
mydate = "2016 12";
date = mydate.ToDateTime("yyyy d"); // {12.01.2016 00:00:00}
mydate = "2016/31/05 13:3...
How To fix white screen on app Start up?
...... apparently someone at Google decided that a white preview window was really awesome to use by default. However, in an app that uses a dark background it's a really bad idea. The solution is to create a custom style for your app and specify 'android:windowBackground' to the color you want to use....
How to run travis-ci locally
... order to run the build. With jenkins you can download jenkins and run locally. Does travis offer something like this?
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What does the unary plus operator do?
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It's there to be overloaded if you feel the need; for all predefined types it's essentially a no-op.
The practical uses of a no-op unary arithmetic operator are pretty limited, and tend to relate to the consequences of using a value in an arithmetic expression, rather than the ...
How to get the nth occurrence in a string?
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I actually don't like this answer. Given an unbounded length input, it needlessly creates an unbounded length array, and then throws most of it away. It would be faster and more efficient just to iteratively use the fromIndex argum...
FileSystemWatcher vs polling to watch for file changes
...n application that watches for files being created in a directory, both locally or on a network drive.
13 Answers
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Can someone explain __all__ in Python?
I have been using Python more and more, and I keep seeing the variable __all__ set in different __init__.py files. Can someone explain what this does?
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