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Why covariance and contravariance do not support value type
IEnumerable<T> is co-variant but it does not support value type, just only reference type. The below simple code is compiled successfully:
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Is there a way to simulate the C++ 'friend' concept in Java?
...n another package without having to make it a subclass of the other class. Is this possible?
19 Answers
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When to use reinterpret_cast?
...en the types can be interpreted at compile time hence the word static . This is the cast the C++ compiler uses internally for implicit casts also.
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How and why does 'a'['toUpperCase']() in JavaScript work?
JavaScript keeps surprising me and this is another instance. I just came across some code which I did not understood at first. So I debugged it and came to this finding:
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Difference between HashMap, LinkedHashMap and TreeMap
What is the difference between HashMap , LinkedHashMap and TreeMap in Java?
I don't see any difference in the output as all the three has keySet and values . What are Hashtable s?
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To Workflow or Not to Workflow?
...answers.
From the description of your business problem it sounds like WF4 is a good match, so no problems there.
Regarding your concerns you are right. Basically WF4 is a new product and is lacking some important features and has some rough edges. There is a learning curve, you do have to do some ...
Method Syntax in Objective-C
Can someone explain this method declaration syntax for me? In this function, the number of rows of a UIPickerView (slot machine UI on the iPhone) is being returned. From my understanding, the Method is called ' pickerView ', and returns an NSInteger.
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What is the most accurate way to retrieve a user's correct IP address in PHP?
...ables headers available for IP address retrieval. I was wondering if there is a general consensus as to how to most accurately retrieve a user's real IP address (well knowing no method is perfect) using said variables?
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Is it possible to make the -init method private in Objective-C?
...hods. Any message can be sent to any object at any time.
What you can do is throw an NSInternalInconsistencyException if your -init method is invoked:
- (id)init {
[self release];
@throw [NSException exceptionWithName:NSInternalInconsistencyException
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Which is faster: Stack allocation or Heap allocation
This question may sound fairly elementary, but this is a debate I had with another developer I work with.
23 Answers
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