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Why is it important to override GetHashCode when Equals method is overridden?
...s equal, it is not necessary for them to be the same; this is a collision, and Equals will be called to see if it is a real equality or not.
In this case, it looks like "return FooId;" is a suitable GetHashCode() implementation. If you are testing multiple properties, it is common to combine them ...
How do you do a deep copy of an object in .NET? [duplicate]
...nto serialization graph, since BinaryFormatter uses fields via reflection, and events are just fields of delegate types plus add/remove/invoke methods. You can use [field: NonSerialized] on event to avoid this.
– Ilya Ryzhenkov
Sep 24 '08 at 20:16
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Difference between left join and right join in SQL Server [duplicate]
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Select * from Table1 left join Table2 ...
and
Select * from Table2 right join Table1 ...
are indeed completely interchangeable. Try however Table2 left join Table1 (or its identical pair, Table1 right join Table2) to see a difference. This query should give you mo...
Is there a rule-of-thumb for how to divide a dataset into training and validation sets?
Is there a rule-of-thumb for how to best divide data into training and validation sets? Is an even 50/50 split advisable? Or are there clear advantages of having more training data relative to validation data (or vice versa)? Or is this choice pretty much application dependent?
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Is key-value observation (KVO) available in Swift?
...mework can help you accomplish what you wanted, rather than using KVO
Yes and no. KVO works on NSObject subclasses much as it always has. It does not work for classes that don't subclass NSObject. Swift does not (currently at least) have its own native observation system.
(See comments for how to ...
C++ include and import difference
What is the difference between #include and #import in C++?
5 Answers
5
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git diff renamed file
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The issue with the difference between HEAD^^ and HEAD is that you have an a.txt in both commits, so just considering those two commits (which is what diff does), there is no rename, there is a copy and a change.
To detect copies, you can use -C:
git diff -C HEAD^^ HEA...
Center/Set Zoom of Map to cover all visible Markers?
I am setting multiple markers on my map and I can set statically the zoom levels and the center but what I want is, to cover all the markers and zoom as much as possible having all markets visible
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How many and which are the uses of “const” in C++?
...y obscure to me, one of these is const . You can use it in so many places and with so many different effects that is nearly impossible for a beginner to come out alive. Will some C++ guru explain once forever the various uses and whether and/or why not to use them?
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Center a position:fixed element
...a position: fixed; popup box centered to the screen with a dynamic width and height. I used margin: 5% auto; for this. Without position: fixed; it centers fine horizontally, but not vertically. After adding position: fixed; , it's even not centering horizontally.
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