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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 ...
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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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()...
ActiveModel::ForbiddenAttributesError when creating new user
...e is an easier way to avoid the Strong Parameters at all, you just need to convert the parameters to a regular hash, as:
unlocked_params = ActiveSupport::HashWithIndifferentAccess.new(params)
model.create!(unlocked_params)
This defeats the purpose of strong parameters of course, but if you are i...
Why doesn't RecyclerView have onItemClickListener()?
I was exploring RecyclerView and I was surprised to see that RecyclerView does not have onItemClickListener() .
32 Ans...
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...
How to get a microtime in Node.js?
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Please check the time units when converting seconds to microseconds. console.log(hrTime[0] * 1000000 + hrTime[1] / 1000)
– itaifrenkel
May 5 '14 at 16:05
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java get file size efficiently
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Well, I tried to measure it up with the code below:
For runs = 1 and iterations = 1 the URL method is fastest most times followed by channel. I run this with some pause fresh about 10 times. So for one time access, using the URL is the fastest way I can think of:
LENGTH sum: 10626, per It...