It is convenient to link elements to each other to perform various operations.

These links are stored in the project. So related elements can then be found, linked, unlinked, etc.

Communication is one-way. Those. one element can be related to another, but this other cannot be related to the first.

Communication is characterized by bits. For example, the number 1 has the last bit set. And the number 2 has the penultimate bit set.

It is possible to establish or break links on these bits at the same time, if you specify the number 3 (both bits are set to 1).

Or separately.

In the course of program execution, you can get related elements, connect them with a two-way connection (from an element to another - 1 and from that to the first - 2).

For these manipulations, there are convenient functions described below.