SMAS 2.0b   A Primer

  6. SMAS Internals (Static structures)

Agents and messages are represented as objects with attributes.

Agent

The agent structure contains the following properties:

   :name                    ; qualifies the agent (external name)
   :input-messages          ; list of input-messages (input tray)
   :output-messages         ; list of output messages (output tray)
   :delayed-output          ; list or results
   :status                  ; :idle :busy or :waiting-for-answer
   :task-in-progress        ; message corresponding to the task being executed
   :pending-tasks           ; subtask list needed when executing the skill
   :skills                  ; list of functions to be applied
   :task-environment        ; left to the user for intermediate results
   :last-subtask-result     ; contains the result returned by a subtask

The agent structure is created by the defagent macro which simply fills in the :name attribute and the :status attribute with the :idle value, all other attributes being empty.

Messages

A message is an object which is created dynamically whenever necessary and has the following attributes:

   :type                   ; message type (:request, :answer)
   :from agent-id          ; if none, assumed to be the user
   :to agent-id            ; if none, assumed to be the user
   :date clock-time        ; time at which the message is produced
   :action function        ; name of agent function to axecute
   :task task-id           ; task name e.g., T-2
   :args list-of-arguments ; arguments for executing the task
   :reply-to agent-id      ; to whom the result is sent (default the sender)
   :contents               ; message content

A message is created by the send-subtask function. Normally the user does not manipulate messages directly.

Copyrignt Jean-Paul Barthès@UTC, 1998 Last update, Jan 99