flex Expert System Toolkit - LPIS

9. Flex Predicates 121
add_value( +Slot,+Term )
add_value/2 can either be used to augment lists or to increment numbers.
The given Term is first dereferenced down to some Value.
The Slot should either be a compound term of the form
@(Attribute,Frame) or it is the name of a global variable, in which case
the name of the frame to be used is global.
If there is an existing slot then it is augmented with Value. Otherwise, a
new slot is created.
Example
all_rules( -Names )
add_value( @(colour,flag), [red,blue,cyan,white] ).
Find the names of all rules in the workspace.
Example
?- all_rules( N ).
N = [prescribe_lomotil,fill_B_from_A]
ancestor(+Frame,-Ancestor)
Ancestor is an ancestor of Frame in the hierarchy, i.e. Ancestor is the
Frame itself, or a parent frame, or a grandparent frame, or a greatgrandparent
frame, etc.
Example
?- ancestor( moby_dick, A ).
A = moby_dick
A = whale
A = mammal
A = animal
A = ocean_dweller
answer(+Name,-Value)
Retrieve the answer given to the question Name. If the question has not yet
been asked, then the call to answer/2 will automatically invoke the
corresponding call to ask/1 to ask the question and obtain an answer.
Examples
?- answer( starter, X ).
X = soup
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