I'm trying to build a wrapper that will allow you to copy structs that have members that disabled copying. The idea is that copying these members will revert them to init.

This is what I have so far:

struct NoCopy(T) {
static assert( !hasElaborateDestructor!T, "NoCopy does not support type " ~ T.stringof ~ " with elaborate destructor" );

    ubyte[T.sizeof] __bytes;

    this(T val) {
        __bytes[] = (cast(const ubyte *)&val)[0..T.sizeof][];

    @property ref inout(T) value() inout nothrow @trusted @nogc {
        return *cast(inout T*)__bytes.ptr;

    this(this) {
        value = T.init;

    void opAssign(NoCopy rhs) {
        value = T.init;

    void opAssign(T rhs) {
        value = move(rhs);

    alias this value;

I'm having problems with setting the initial value for the byte array. The technique I use in "value" does not work for initialization:

test.d(19): Error: cannot convert &S to const(ubyte*) at compile time

At first, I said "fine, the user will do it". That doesn't work, however. It doesn't matter who tries to do it, I cannot get the byte value of the type at compile time.

I tried using a union, but that, too, doesn't work.

I understand why the restriction is in place. What I'm wondering is whether there is any other solution, either to the init problem or to the overriding disable problem.

Thank you,

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