Good question! It’s not listed one way or another in the list of overloadable and non-overloadable operators and nothing’s mentioned on the operator’s page. So I tried the following: public class TestClass { public static TestClass operator ??(TestClass test1, TestClass test2) { return test1; } } and I get the error “Overloadable binary operator expected”. … Read more
In Ruby, the short-circuiting Boolean operators (||, &&, and and or) do not return true or false, but rather the first operand that determines the outcome of the entire expression. This works, because Ruby has a rather simple idea of truth. Or rather, it has a rather simple idea of falsehood: nil is false, and … Read more
PHP 7 adds the null coalescing operator: // Fetches the value of $_GET[‘user’] and returns ‘nobody’ // if it does not exist. $username = $_GET[‘user’] ?? ‘nobody’; // This is equivalent to: $username = isset($_GET[‘user’]) ? $_GET[‘user’] : ‘nobody’; You could also look at short way of writing PHP’s ternary operator ?: (PHP >=5.3 only) … Read more
Using null-coalescing operator ( ?? ): get { _rows = _rows ?? new List<Row>(); return _rows; } OR (less readable): get { return _rows ?? (_rows = new List<Row>()); } The ?? operator is called the null-coalescing operator. It returns the left-hand operand if the operand is not null; otherwise it returns the right hand … Read more
I’m tempted to lie and say that English is my second language…but the truth is that I just have no idea what ‘Coalescing’ means. I know what ?? ‘does’ in C#, but the name doesn’t make sense to me. I looked up the word and I understand it to be a synonym for ‘join’. I’d … Read more
Okay, I have done some thinking and testing. This is what happens: int value = nullableInt?.Value; Gives this error message when compiling: Type ‘int’ does not contain a definition for `Value’ That means that ? ‘converts’ the int? into the actual int value. This is effectively the same as: int value = nullableInt ?? default(int); … Read more
Yes, there is, a long as you’re using VB 9 or later (included with Visual Studio 2008). You can use the version of the If operator overloaded to accept only two arguments: Dim myVar? As Integer = Nothing Console.WriteLine(If(myVar, 7)) More information can be found here in a blog post by the VB.NET team. (Yes, … Read more
Coalescing is performed via || operator, i.e. let str:string = name || FirstName || “name is null and FirstName is null”; You can also read this question for more details and explanations.
This is a null coalescing operator. The method above states x is assigned y’s value, unless y is null, in which case it is assigned z’s value.
Step by step explanation: params Delegate?[] delegates – It is an array of nullable Delegate params Delegate?[]? delegates – The entire array can be nullable Since each parameter is of the type Delegate? and you return an index of the Delegate?[]? array, then it makes sense that the return type is Delegate? otherwise the compiler … Read more