R152 - modelint/flatland-model-diagram-editor GitHub Wiki
R152 / 1:M
Tree Connector radiates out to one or many Leaf Stem
Leaf Stem sproutes from exactly one Tree Connector
While there is only one Trunk Stem in a Tree Connector, there may be one or more Leaf Stems to form a hierarchical pattern. By policy, the pattern does not support a leaf-less tree.
In the example of a class diagram generalization relationship, each subclass would extend a Leaf Stem to attach to a Branch in the Tree Connector.