ALLOCATED
void _Unset() { if (fVersion & ALLOCATED) delete fKey; fKey = NULL; }
: fKey(new(nothrow) Key(*k.fKey)), fVersion(k.fVersion | ALLOCATED) {}
fVersion = KEY_FORMAT_3_5 | ALLOCATED;
fVersion = KEY_FORMAT_3_6 | ALLOCATED;
if (!(fVersion & ALLOCATED))
fVersion |= ALLOCATED;
fVersion |= ALLOCATED;
fVersion |= ALLOCATED;
if (fVersion & ALLOCATED) {