The SEDRIS Data Representation Model
APPENDIX B - Constraints
State Related Organizing Principle

Definition

For any state-related aggregation SRA, whether a <State Related Features> or a <State Related Geometry>,

  1. The state_tag of SRA shall be "state-applicable".

  2. Each branch of SRA shall comply with the following constraints.

    2.1 The <State Data> associated with that branch shall have a state_value, the attribute_value_type of which matches that of SRA's active_state_value.
    2.2 The <State Data> associated with that branch shall have a state_value which does not overlap with that of any other branch's <State Data> within SRA.
  3. If SRA has a <State Control Link> instance as a component, then the return type of each of the <Expression> components of the <State Control Link> shall match that of SRA's active_state_value's attribute_value_type.

Rationale

  1. The state_tag shall specify some EAC that is actually legal for use as a state.

  2. The active_state_value, and each of the possible <State Data> instances' state_values, as well as the return types of the <State Control Link> instance's <Expression> components (if any) are all designed to be interchangeable, since any one of them could determine the active state of SRA at some point.

  3. The values specified by the <State Data> instances may not overlap, because the active_state_value shall unambiguously specify which state that SRA is in.

Example

No Example supplied.

FAQs

No FAQs supplied.


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Last updated: July 16, 2004 Copyright © 2004 SEDRIS