Use Case: Key Hierarchy

Summary

• Scope: libelektra-core
• Level: Developer Goal
• Actors: Core, Caller
• Brief: Hierarchy comparison between Key's

Scenarios

• Precondition:
  • `Key` K1 has been created
  • `Key` K2 has been created
• Main success scenario:
  • Caller reads names N1 and N2 of Key K1 and Key K2
  • Caller requests hierarchy comparison between N1 and N2
  • Core returns one of these results
    • N1 and N2 do not form a hierarchy
    • N1 is the same as N2
    • N2 is a direct child of N1 in the hierarchy
    • N2 is a descendant of N1 in the hierarchy
• Alternative scenario: -
• Error scenario: -
• Postcondition: -
• Non-functional Constraints:
  • The hierarchy comparison MUST form a partial order over Keys.
  • Each of the possible results MAY be a single value, but it MAY also be a whole class of value (e.g. negative integer).