Re: How do I find the actual types of the elements in a list of classes?

[rumbu via Digitalmars-d-learn]

On Thursday, 13 August 2015 at 21:42:54 UTC, Jack Stouffer wrote:

Thanks, that worked, and based on your answer, I was able to fix my real problem: dynamically calling different methods on each object in the list based on its type. So, using the above code as an example, I am able to call method if the object is of type A and method2 if the object is of type B:

interface Parent {
        void method();
}

class A : Parent {
        void method() {}

        this() {}
}

class B : Parent {
        void method() {}
        void method2() {}

        this() {}
}

void main() {
        import std.stdio;
        import std.string;

        Parent[] parent_list = [];
        parent_list ~= new A();
        parent_list ~= new B();

        foreach (item; parent_list) {

string class_name = (cast(Object) item).classinfo.name;

                if (class_name == "test.A") {
                        (cast(A) item).method();
                } else if (class_name == "test.B") {
                        (cast(B) item).method2();
                }
        }
}

This is a dirty hack, but I don't care, it works :)

It works as long as your module is called "test".

I think this is a better approach:

foreach (item; parent_list) {
        if (auto a = cast(A)item)
            a.method();
        else if (auto b = cast(B)item)
            b.method2();
    }