impl_holder.held = new WriteableScore(null, ptr_idx[0]);
impl_holder.held.instance_idx = ptr_idx[1];
impl_holder.held.bindings_instance = structImplementation;
impl_holder.held.ptrs_to.push(lockableScore);
impl_holder.held = new WriteableScore(null, ptr_idx[0]);
impl_holder.held.instance_idx = ptr_idx[1];
impl_holder.held.bindings_instance = structImplementation;
impl_holder.held.ptrs_to.push(lockableScore);