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Unable to Cast from Parent Class to Child Class
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Well, I would hesitate to call this a "downcast".
– Kirk Woll
Dec 24 '12 at 4:43
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In Eclipse, what can cause Package Explorer “red-x” error-icon when all Java sources compile without
I'm using Eclipse for Java development. All my sources compile fine and the resulting application compiles fine. However, I keep getting an "red-x" error notification in the Package Explorer.
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When to use .First and when to use .FirstOrDefault with LINQ?
I've searched around and haven't really found a clear answer as to when you'd want to use .First and when you'd want to use .FirstOrDefault with LINQ.
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Null or default comparison of generic argument in C#
...IEquatable<T> (without boxing) as well as object.Equals, and handles all the Nullable<T> "lifted" nuances. Hence:
if(EqualityComparer<T>.Default.Equals(obj, default(T))) {
return obj;
}
This will match:
null for classes
null (empty) for Nullable<T>
zero/false/etc for...
Regular expression for first and last name
... I would escape the special characters in these regexps - especially . (decimal point/dot/full stop) since it's the regexp wildcard =)
– Joel Purra
Aug 8 '12 at 18:45
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Is it smart to replace boost::thread and boost::mutex with c++11 equivalents?
...ried explaining the quality of boost, then gave up after some time :( ). Smaller reason why I would like to do it is that I would like to learn c++11 features, because people will start writing code in it.
So:
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Correct way to close nested streams and writers in Java [duplicate]
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I usually do the following. First, define a template-method based class to deal with the try/catch mess
import java.io.Closeable;
import java.io.IOException;
import java.util.LinkedList;
import java.util.List;
public abstract cl...
Gson - convert from Json to a typed ArrayList
... convert a JSON string to an ArrayList of a custom class JsonLog ? Basically, JsonLog is an interface implemented by different kinds of logs made by my Android app--SMS logs, call logs, data logs--and this ArrayList is a collection of all of them. I keep getting an error in line 6.
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float64 with pandas to_csv
...mvent this problem, I recommend you create another CSV file which contains all figures as integers, for example multiplying by 100, 1000 or other factor which turns out to be convenient. Inside your application, read the CSV file as usual and you will get those integer figures back. Then convert tho...
Do declared properties require a corresponding instance variable?
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In your interface, you can formally declare an instance variable between the braces, or via @property outside the braces, or both. Either way, they become attributes of the class. The difference is that if you declare @property, then you can implement usin...