Re: Template mixins and struct constructors

[Adrian Matoga via Digitalmars-d-learn]

On Wednesday, 2 March 2016 at 14:36:59 UTC, Daniel Kozak wrote:
OK maybe this one:
template AddField(T) {
    T b;
    this(Args...)(T b, auto ref Args args)
    {
           this.b = b;
       this(args);
    }
    this(int a) {
        this.a = a;
    }
}

struct Bar {
    int a;
    mixin AddField!(string);
}

unittest {
    auto bar1 = Bar(5);
    auto bar2 = Bar("bar", 15);
}

Then it's limited to structs in which only "int a" is to be 
initialized. Not very useful and the templated ctor is not needed 
now.

struct Baz {
    mixin AddField!string; // fail, no "int a" in Baz.
    ulong d;
    double x;
    string foo;
}