Patt#16. "Group-Member" Pattern // aggregate patterns

Typical object interactions
- howMany --> calcForMe
- calcOverMembers --> calcForMe
- rankMembers --> rateMe
Examples
- company-employee; team - team member.
Combinations
Also, when "group" or "member" is a participant, place, or
specific item:
Related strategy: Str#37.
"Select and Reuse a Group of Interacting Objects" Strategy
Aggregate patterns
Patterns for building object
models