Optional parameters are an attribute of a method or delegate parameter. When you call a signature (method or delegate) that has a known optional parameter at compile-time, the compiler will insert the optional parameter value at the callsite. The runtime is not aware of optional parameters, so you can’t make a delegate that inserts an … Read more
The C# compiler doesn’t use the [DefaultParameterValue] attribute to set the default value, it uses the .param directive to get the value embedded in the metadata. Barely documented in the CLI spec btw, only Partition II, chapter 15.4.1 mentions that it can have a FieldInit value, 15.4.1.4 is silent about it. That’s where the buck … Read more
You can have default template arguments, which are sufficient for your purposes: template<class T, class U = T, class V = U> class Test { }; Now the following work: Test<int> a; // Test<int, int, int> Test<double, float> b; // Test<double, float, float>
You could do something like this: protected static object[] Args(params object[] args) { return args; } protected void Log(string message, object[] args = null, [CallerMemberName] string method = “”) { // Log } To use the log do like this: Log(“My formatted message a1 = {0}, a2 = {2}”, Args(10, “Nice”));
Only component in which parameter is added was build an deployed as patch. The calling component is old as there is no change in it. There should be a change in it, because the old code calls a method which no longer exists! As far as i know it should not raise an error as … Read more
The problem with optional arguments in C# is whether the callee sees the object as a TestClass or an ITestInterface. In the first case, the values declared in the class apply. In the second case the values declared in the interface apply. It is because the compiler uses the statically available type information to construct … Read more
Yes: void foo(a::really::long::type::name arg = {}); To sum up the following standard definitions: This is list initialization. Depending of the type, aggregate initialization is performed or the object is value initialized, which in turn implies default initialized or zero initialized. Some “corner” cases are when the type is a specialization of std::initializer_list or when the … Read more
Here’s another solution, partly inspired by Chris’ answer. It also involves a wrapper, but the wrapper is transparent, you only have to define it once, and the user of the API doesn’t need to import any conversions: class Opt[T] private (val option: Option[T]) object Opt { implicit def any2opt[T](t: T): Opt[T] = new Opt(Option(t)) // … Read more
Your only option right now is to overload the TestOptional (as you had to do before C# 4). Not preferred, but it cleans up the code at the point of usage. public static void TestOptional(string A, params string[] C) { TestOptional(A, 0, C); } public static void TestOptional(string A, int B, params string[] C) { … Read more