flex Expert System Toolkit - LPIS

11. Example – Robbie Goes Shopping 161
frame medium_item is an item
default size is medium .
frame small_item is an item
default size is small .
The medium_item and small_item frames automatically inherit 3 as the
value for maximum_allowed, whereas the large_item frame overrides
this value with 1.
The following KSL sentences define the characteristics of each shopping
item.
frame bread is a medium_item
default container is a plastic_bag and
default condition is fresh .
frame butter is a small_item
default container is a plastic_carton and
default condition is fresh .
frame coffee is a medium_item
default container is a jar and
default condition is freeze_dried .
frame ice_cream is a medium_item
default container is a cardboard_carton and
default condition is frozen .
frame crisps is a small_item
default container is a plastic_bag and
default condition is fragile .
frame salted_peanuts is a small_item
default container is a plastic_bag and
default condition is salted .
frame beer is a large_item
default container is a bottle and
default condition is liquid .
frame lemonade is a large_item
default container is a bottle and
default condition is liquid .
frame washing_powder is a large_item
default container is a cardboard_carton and
default condition is powder .
The KSL rules for packing the items into bags are hopefully self explanatory.
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