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One-liner to check whether an iterator yields at least one element?
... iterator in case any_check ever needs to advance. This is worse than just converting the original iterator to a list.
– Rafał Dowgird
Mar 3 '11 at 8:54
1
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Why would an Enum implement an Interface?
...e.g. colours). They can represent more complex objects with functionality, and so you're then likely to want to add further functionality to these - e.g. you may have interfaces such as Printable, Reportable etc. and components that support these.
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When to use Comparable and Comparator
...thought I wrote a new class that implements Comparator, that does the task and it works.
19 Answers
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Entity Framework Code First - two Foreign Keys from same table
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@NickW: That is something you have to handle in your application and not in the mapping. From the mapping perspective, pairs are allowed to play twice (each is guest and home once).
– Ladislav Mrnka
Jun 8 '13 at 22:08
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Android List View Drag and Drop sort
...ords in a listview that I want the user to be able to re-sort using a drag and drop method. I have seen this implemented in other apps, but I have not found a tutorial for it. It must be something that others need as well. Can anyone point me to some code for doing this?
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How do I get the first element from an IEnumerable in .net?
...often want to grab the first element of an IEnumerable<T> in .net, and I haven't found a nice way to do it. The best I've come up with is:
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Why does this code using random strings print “hello world”?
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When an instance of java.util.Random is constructed with a specific seed parameter (in this case -229985452 or -147909649), it follows the random number generation algorithm beginning with that seed value.
Every Random constructed with the same seed will ...
Run two async tasks in parallel and collect results in .NET 4.5
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You should use Task.Delay instead of Sleep for async programming and then use Task.WhenAll to combine the task results. The tasks would run in parallel.
public class Program
{
static void Main(string[] args)
{
Go();
}
public static void Go()...
Why can't I make a vector of references?
... not assignable (you can only initialize them once when they are declared, and you cannot make them reference something else later). Other non-assignable types are also not allowed as components of containers, e.g. vector<const int> is not allowed.
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Is there a way to instantiate objects from a string holding their class name?
...<DerivedA>;
map["DerivedB"] = &createInstance<DerivedB>;
And then you can do
return map[some_string]();
Getting a new instance. Another idea is to have the types register themself:
// in base.hpp:
template<typename T> Base * createT() { return new T; }
struct BaseFactor...