Re: How to get child class Type and members from parent class?

[Jacob Carlborg via Digitalmars-d-learn]

On Wednesday, 20 November 2019 at 10:05:11 UTC, zoujiaqing wrote:

import std.stdio;


class A
{
    this(T)(T t)
    {

    }

    void write()
    {
        T _this = cast(T) this;
        writeln(this.v);
    }
}

class B : A
{
    string v = "hello";
}

void main()
{
    auto b = new B;

    writeln(b.write()); // print hello
}

You can use a template this parameter [1], like this:

import std.stdio;

class A
{
    void write(this T)()
    {
        T self = cast(T) this;
        writeln(self.v);
    }
}

class B : A
{
    string v = "hello";
}

void main()
{
    auto b = new B;
    b.write();
}

[1] https://dlang.org/spec/template.html#template_this_parameter

--
/Jacob Carlborg