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Should a retrieval method return 'null' or throw an exception when it can't produce the return value
...uld mean that there was a problem.
If the value can be missing or present and both are valid for the application logic then return a null.
More important: What do you do other places in the code? Consistency is important.
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How to initialize std::vector from C-style array?
...you just need a one time initialization, you can put it in the constructor and use the two iterator vector constructor:
Foo::Foo(double* w, int len) : w_(w, w + len) { }
Otherwise use assign as previously suggested:
void set_data(double* w, int len)
{
w_.assign(w, w + len);
}
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Big-oh vs big-theta [duplicate]
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Big-O is an upper bound.
Big-Theta is a tight bound, i.e. upper and lower bound.
When people only worry about what's the worst that can happen, big-O is sufficient; i.e. it says that "it can't get much worse than this". The tighter the bound the better, of course, but a tight bound isn't...
Positioning MKMapView to show multiple annotations at once
...ine, but I want to resize the map to fit all annotations onscreen at once, and I'm not sure how to do this.
24 Answers
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Initializing a static std::map in C++
... implements these utilities is that it is neatly encapsulated in a library and the end user rarely needs to deal with the complexity.
– Steve Guidi
Nov 13 '09 at 18:09
45
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Where is Java's Array indexOf?
I must be missing something very obvious, but I've searched all over and can't find this method.
13 Answers
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What is Delegate? [closed]
...til runtime. So you use a "delegate" for that purpose. Delegates come in handy for things like event handlers, and such, where you do different things based on different events, for example.
Here's a reference for C# you can look at:
In C#, for example, let's say we had a calculation we wanted to...
Purpose of returning by const value? [duplicate]
... this operation on a temporary. Imagine that + returned a non-const value, and you could write:
(a + b).expensive();
In the age of C++11, however, it is strongly advised to return values as non-const so that you can take full advantage of rvalue references, which only make sense on non-constant r...
Base64 encoding in SQL Server 2005 T-SQL
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The simplest and shortest way I could find for SQL Server 2012 and above is BINARY BASE64 :
SELECT CAST('string' as varbinary(max)) FOR XML PATH(''), BINARY BASE64
For Base64 to string
SELECT CAST( CAST( 'c3RyaW5n' as XML ).value('.',...
Difference between std::result_of and decltype
I have some trouble understanding the need for std::result_of in C++0x. If I understood correctly, result_of is used to obtain the resulting type of invoking a function object with certain types of parameters. For example:
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