A reference is a mechanism by which information in a node is related to, or accessed by, other nodes. The ability of a node to establish a reference with another node enables the first to access the information or features entailed in the second one.
References have a direction property relative to each of the nodes involved in the reference: the node establishing the reference sets an outgoing reference, while the one accepting the reference sets an incoming reference.
For example, a session establishes an outgoing reference with a trading system. This allows the session to access the information within the whole trading system hierarchy, including strategies. At the trading system level, the same reference is viewed as an incoming reference.
A reference established between nodes of any particular structure within a hierarchy is said to be an internal reference relative to the said structure of nodes. Similarly, a reference established with a node outside of the said structure, that is, in a different part of the hierarchy or in another hierarchy, is said to be an external reference.
Examples of internal references may be found in the data mine and crypto ecosystem hierarchies. For example, let’s briefly look into one such case within a plotter module:
This means that the node shapes feature several internal references.
Establishing and Removing References
To establish a reference, right-click on the first node and drag it close to the target node. Grey rings show which nodes you may establish a reference with. In case there are multiple nodes that would accept the reference, the one closer to the node where the reference originates will have its ring highlighted. Releasing the mouse button establishes the reference, or links both nodes.
The reference is visually represented by a faint grey dotted line. Such line is visible only when both ends of the reference are visible.
To remove a reference or delink two nodes, simply right-click the node where the reference originates and make a dentle swipping motion away from the target node.