problem with deleting list item in prolog

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my code in prolog

:- dynamic kitchenfurniture/1.

kitchenfurniture([furniture(fridge,1), furniture(table,2), furniture(chair,1)]).

writel([H|T]) :- write(H), nl, writel(T).

whatkitchenfurniture :- kitchenfurniture(X), writel(X).

addkitchenfurniture(X) :- kitchenfurniture(Y), append(Y, [X], Z), retract(kitchenfurniture(Y)), assert(kitchenfurniture(Z)).

deletekitchenfurniture(X) :- kitchenfurniture(Y), delete(X, Y, Z),  retract(kitchenfurniture(Y)), assert(kitchenfurniture(Z)).

when I enter the code in the console

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it does not remove the item from the list

problem wth line code deletekitchenfurniture(furniture(fridge,1)).

1 Answers

It is difficult to understand what exactly you type into the console; why don't you show it?

It is probable that this is wrong:

?- deleteaddkitchenfurniture('furniture(fridge,1)').

The correct way to do it might be:

?- deleteaddkitchenfurniture(furniture(fridge,1)).

No single quotes there. If you put it in single quotes, it becomes an atom with some parentheses embedded in it. If you don't quote, it is a compound term, as in the original list you have in here:

kitchenfurniture([furniture(fridge,1), furniture(table,2), furniture(chair,1)]).
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