Variable
A named container whose value contributes to the definition of State.
h/ai Primitive Language
Volume II
Domain Primitives
Domain primitives define the structure, constraints, and completion of an interaction space independently of implementation technology.
Overview
The Domain family defines the structure of interaction. It specifies the variables, relationships, constraints, states, and events that collectively describe a particular interaction space.
Domain primitives answer the question: What exists within this interaction?
Primitive Definitions
Type
The allowable form and range of values for a Variable.
Relationship
An association between Variables, States, or other Domain elements.
Constraint
A rule limiting the allowable values or relationships within a Domain.
Validation
The evaluation of Domain values against defined Constraints.
Completion
The condition indicating that Domain requirements have been satisfied.
State
The complete set of Variable values at a specific point in interaction.
Event
An occurrence that may create or modify State.
Example: Restaurant Order
Variables Bagel Spread Toast ↓ Constraint Bagel required ↓ Validation Spread selected ↓ Completion Order ready ↓ State Submit Order
Domain Principle
Every interaction occurs within one or more Domains. A Domain defines the permissible structure of State, the relationships between Variables, and the conditions under which interaction is considered complete.