import core.memory : pureMalloc, pureFree;

import std.algorithm : move, moveEmplace;

import std.traits : hasElaborateDestructor;

​

struct NonCopyable {

    this(this) @disable;

}

​

struct Unique(T) {

    this(this) @disable;

    T* m_data;

    this(T data) {

        m_data = cast(T*) pureMalloc(T.sizeof);

        moveEmplace(data, *m_data);

    }

    ~this() {

        if(m_data) {

            static if(hasElaborateDestructor!T) (cast(Unqual!T*) m_data).__xdtor;

            pureFree(m_data);

        }

    }

}

​

void main() {

    NonCopyable a;

    auto ua = Unique!NonCopyable(move(a)); // fine

​

    const NonCopyable const_a;

    auto const_ua = Unique!(const NonCopyable)(move(ca)); // error, why???

}