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C#: Assign same value to multiple variables in single statement
...nteresting to know that the get accessor of the intermediate value is not called. Only the set accessor is invoked for all property accessed in the assignation sequence.
Take for example a class that write to the console everytime the get and set accessor are invoked.
static void Main(string[] arg...
boost::flat_map and its performance compared to map and unordered_map
...e, because your cache will not be warm, and your operation will likely be called just once. Therefore you need to benchmark using RDTSC, and time stuff calling them once only.
Intel has made a paper describing how to use RDTSC (using a cpuid instruction to flush the pipeline, and calling it at least...
Combining two expressions (Expression)
...m);
}
Starting from .NET 4.0, there is the ExpressionVisitor class which allows you to build expressions that are EF safe.
public static Expression<Func<T, bool>> AndAlso<T>(
this Expression<Func<T, bool>> expr1,
Expression<Func<T, bool>&...
Why can't I define a default constructor for a struct in .NET?
...type a default constructor is created (by the compiler?) which initialized all members to zero (or null ).
10 Answers
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What's the algorithm to calculate aspect ratio?
...re that's been changed from 16:9 to 5:4 - I still remember the incredibly tall, thin cowboys I used to watch in my youth on television before letter-boxing was introduced. You may be better off having one different image per aspect ratio and just resize the correct one for the actual screen dimensio...
Cannot delete or update a parent row: a foreign key constraint fails
... (`advertiser_id`)
REFERENCES `jobs` (`advertiser_id`);
...is actually the opposite to what it should be. As it is, it means that you'd have to have a record in the jobs table before the advertisers. So you need to use:
ALTER TABLE `jobs`
ADD CONSTRAINT `advertisers_ibfk_1` FOREIGN KEY...
List of lists changes reflected across sublists unexpectedly
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When you write [x]*3 you get, essentially, the list [x, x, x]. That is, a list with 3 references to the same x. When you then modify this single x it is visible via all three references to it:
x = [1] * 4
l = [x] * 3
print(f"id(x): {id(x)}")
# id(x): 1405608979...
Objective-C declared @property attributes (nonatomic, copy, strong, weak)
... retaining the copy.
Assign
Assign is somewhat the opposite to copy. When calling the getter of an assign property, it returns a reference to the actual data. Typically you use this attribute when you have a property of primitive type (float, int, BOOL...)
Retain
retain is required when the attribut...
How to detect that animation has ended on UITableView beginUpdates/endUpdates?
...ates . I am also using beginUpdates/endUpdates when adjusting rowHeight. All these operations are animated by default.
7 ...
How to get the Power of some Integer in Swift language?
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I really like this solution, but with Swift 3 it does not work. Any idea how to make it work?
– Vanya
Sep 19 '16 at 18:51
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