A helper function for Rebindable!() can help remove some noise from the code, this is a first try:


import std.typecons, std.traits;

template isImmutable(T) {
    enum bool isImmutable = is(const(T) == T) || is(immutable(T) == T);
}

Rebindable!T rebindable(T)(T obj)
  if ((is(T == class) || is(T == interface) || isArray!T) && isImmutable!T) {
    return Rebindable!T(obj);
}

// usage example
import std.stdio;
class Foo {}
void main() {
    auto a = rebindable(new immutable(Foo));
    assert(a.sizeof == 4);
    a = new immutable(Foo);
}


I don't know if isImmutable!() works well in all cases, I have not tested it much. But a template like isImmutable can be useful in Phobos.