Clears all values from the given relation of a given frame.


The frame on which the relation occurs.
The relation (also called a slot or property) on the frame.


  (:CLEAR-RELATION Rover HasFleas)
  (:CLEAR-RELATION WhiteHouse Owner)

Success criteria

Always succeeds if the frame is a frame and if the relation is a relation.

Failure criteria

Fails only if one or more of the arguments does not exist.


This command removes all values of the relation (also called a slot or property). Use :DELETE to delete one specific value.

This command should be used with care. Even though relation values are deleted, inferences made from those values are not deleted. Algernon does not currently support non-monotonic reasoning.

Related commands

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