[C++] Indexing table instance

[penyung]

Hi all,
I have a table that is widely used by other tables. I want to index some of table instances by its offset from buffer start and save in a vector so that receiver can quickly access these instances without traversing from root. I want to know what's the best way to do indexing.

Offset<T> is not suitable to be index by the documents.
One possible solution is using GetTemporaryPointer to obtain the pointer and calculate the offset when creating the table, but its comments say "Creating new objects will lead to reallocations and invalidates the pointer". So it doesn't seem to work.

I guest the best way is do indexing by traversing root after finishing the whole fbs?

[penyung]

I think my true problem is how to get offset from buffer start when building table instance.
It seems there is no way to get final value when building.