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What does LINQ return when the results are empty
I have a question about LINQ query. Normally a query returns a IEnumerable<T> type. If the return is empty, not sure if it is null or not. I am not sure if the following ToList() will throw an exception or just a empty List<string> if nothing found in IEnumerable result?
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How to exit an if clause
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Ideally you can achieve both, but there are times when you must trade good code for good performance. Those times are rare, especially when you are considering using Python. In other words: don't worry so much about function c...
No identities were available - administrator request
...one)
In your project's build settings update your code signing identities (all of them) to the new one if there is one. (The old one was probably expired which is one of the biggest causes for the error message you saw)
Verify that your bundle ID is correct (CaSe SeNsEtIvE)
Back to XCode Organizer -...
Static constant string (class member)
...files
const string A::RECTANGLE = "rectangle";
The syntax you were originally trying to use (initializer inside class definition) is only allowed with integral and enum types.
Starting from C++17 you have another option, which is quite similar to your original declaration: inline variables
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How to add extension methods to Enums
... methods for existing classes in a way other people on your team might actually discover and use. Given that enums are classes like any other it shouldn’t be too surprising that you can extend them, like:
enum Duration { Day, Week, Month };
static class DurationExtensions
{
public static Date...
Are Roslyn SyntaxNodes reused?
...tions of the tree that were affected by the edit.
Now when you try to put all five of those things into one data structure you immediately run into problems:
How do you build a node in the first place? The parent and the child both refer to each other, and are immutable, so which one gets built f...
What techniques can be used to define a class in JavaScript, and what are their trade-offs?
... this.name = name;
this.gender = gender;
}
// Add methods like this. All Person objects will be able to invoke this
Person.prototype.speak = function(){
alert("Howdy, my name is" + this.name);
};
// Instantiate new objects with 'new'
var person = new Person("Bob", "M");
// Invoke methods...
Is it possible to program iPhone in C++
I'm all for language diversity, but Objective C is insane. So I'm curious: is it possible to code iPhone apps with C++ while using the Cocoa API, etc?
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Should flux stores, or actions (or both) touch external services?
Should the stores maintain their own state and have the ability to call network and data storage services in doing so ...in which case the actions are just dumb message passers,
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Difference between null and empty (“”) Java String
... String("");
System.out.println(a==b);
That would output false because I allocated two different objects, and a and b point to different objects.
However, a.equals(b) in this case would return true, because equals for Strings will return true if and only if the argument String is not null and rep...