A distinguishing feature of the Go programming language is static interfaces that do not need to be explicitly inherited. Using D's compile-time reflection and code generation capabilities, we can do something similar.
Let's start by defining a goal. We'll write an interface and a struct block that could implement the interface, but which does not explicitly inherit from it (the struct blocks in D can not inherit from the interfaces at all). We'll also write the following brief function that uses the interface to perform a task:
interface Animal {
void speak();
void speak(string);
}
struct Duck {
void speak() {
import std.stdio;
writeln("Quack!");
}
void speak(string whatToSay) {
import std.stdio;
writeln("Quack! ", whatToSay);
}
}
void callSpeak(Animal a) {
a.speak();
a.speak("hello");
}
void main() {
Duck d;
// callSpeak(wrap!Animal(&d)); // we want to make this line work
}The callSpeak...