I haven’t personally come across a desire to constrain the types within data types I’ve created, but it’s not obvious to me why the language designers “decided it was a bad idea to allow”. Why is that? Because it was misleading and worked completely backwards from what would actually be useful. In particular, it didn’t … Read more
I don’t understand why all the answers to that question are the same. There are several ways to calculate the square root from a number. One of them was proposed by Isaac Newton. I’ll only write one of the simplest implementations of this method. I use it to improve the accuracy of double’s square root. … Read more
The null coalescing operator has very low precedence so your code is being interpreted as: int? x = 10; string s = (“foo” + x) ?? (0 + “bar”); In this example both expressions are strings so it compiles, but doesn’t do what you want. In your next example the left side of the ?? … Read more
newObjectType is an instance of the Type class (containing metadata about the type) not the type itself. This should work var newObject = givenObject as MyClass; OR var newObject = (MyClass) givenObject; Casting to an instance of a type really does not make sense since compile time has to know what the variable type should … Read more
Assuming the question is about Go, e.g. var _ foo.RequiredInterface = myType{} // or &myType{} or [&]myType if scalar as a TLD will check that for you at compile time.
Your function has a couple of smallint parameters. But in the call, you are using numeric literals that are presumed to be type integer. A string literal or string constant (‘123’) is not typed immediately. It remains type “unknown” until assigned or cast explicitly. However, a numeric literal or numeric constant is typed immediately. The … Read more
This is a very good question! First, let me assure you that you can safely specify the return type. Now, let’s look into it… yes, when left to inference, Scala infers java.lang.String, instead of just String. So, if you look up “String” in the ScalaDoc, you won’t find anything, which seems to indicate it is … Read more
Here is an approach that does not deal with class names at all, and dispatches as fast as a switch statement does: make a hash map to map Class<T> objects to class-specific handlers, and use the map instead of a switch: // Declare an interface for your polymorphic handlers to implement. // There will be … Read more
Short answer: Go ahead, nothing bad will happen. Long answer: The C++ standard extensively protects the ::std namespace in C++11 17.6.4.2.1, but specifically allows your case in paragraphs 1 and 2: The behavior of a C++ program is undefined if it adds declarations or definitions to namespace std or to a namespace within namespace std … Read more
int (*getFunc())(int, int) { … } That provides the declaration you requested. Additionally, as ola1olsson notes, it would be good to insert void: int (*getFunc(void))(int, int) { … } This says that getFunc may not take any parameters, which can help avoid errors such as somebody inadvertently writing getFunc(x, y) instead of getFunc()(x, y).