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Sending a message to nil in Objective-C
...x:i]; This will also return 0, but since objectAtIndex: returns a pointer, and a pointer to 0 is nil/NULL, NSLog will be passed nil each time through the loop. (Although NSLog is a function and not a method, it prints out (null) if passed a nil NSString.
In some cases it's nicer to have a NullPoint...
Why is 'false' used after this simple addEventListener function?
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@BikashChandraMondal check out the answer below.
– libra
Nov 20 '14 at 3:21
34
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Finding the average of a list
...sum(l) / float(len(l))
There is no need to use reduce. It is much slower and was removed in Python 3.
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Can an abstract class have a constructor?
... what) {
super(what);
}
}
The superclass Product is abstract and has a constructor. The concrete class TimesTwo has a constructor that just hardcodes the value 2. The concrete class TimesWhat has a constructor that allows the caller to specify the value.
Abstract constructors will fre...
Making git diff --stat show full file path
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The git diff command takes optional values for --stat:
--stat[=<width>[,<name-width>[,<count>]]]
Generate a diffstat. You can override the default output width for
80-column terminal by --stat=<width>. T...
If using maven, usually you put log4j.properties under java or resources?
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src/main/resources is the "standard placement" for this.
Update: The above answers the question, but its not the best solution. Check out the other answers and the comments on this ... you would probably not shipping your own logging properties with the...
c++ boost::multi_index composite keys efficiency - c++1y / stl - 清泛IT社区，为创新赋能！
...ime poster! I'm playing around with the boost::multi_index container stuff and have a rather in-depth question that hopefully a boost or C++ container expert might know (my knowledge in C++ containers is pretty basic). For reference, the boost documentation on composite keys can be found here: boost...
How to iterate over a JSONObject?
...der doesn't matter in maps of properties: keys in JSONObject are unordered and your assertion was a simple reflection of a private implementation ;)
– caligari
Oct 1 '13 at 13:55
6...
What is a thread exit code?
...for this value could interpret it to mean that the thread is still running and continue to test for the completion of the thread after the thread has terminated, which could put the application into an infinite loop.
My understanding of all this is that the exit code doesn't matter all that much...
Disposing WPF User Controls
...sed by a third party. My control has a private member which is disposable, and I would like to ensure that its dispose method will always get called once the containing window/application is closed. However, UserControl is not disposable. I tried implementing the IDisposable interface and subscribin...