我如何能够在Prolog中打印出Fact的值？

I have the following Prolog rule that allows the user to input three values and assert a Fact from those values:

我有以下Prolog规则,允许用户输入三个值并从这些值断言事实:

input(X,Y,Z) :- Fact = ves(X,Y,Z), assertz(Fact).

How would I now be able to print out the values of the 'ves' Fact? I tried this, however I receive a singleton error for X,Y and Z. I would like the 'checkCap' rule to print the values of 'ves'.

我现在如何能够打印出'ves'事实的价值?我试过这个,但是我收到了X,Y和Z的单例错误。我希望'checkCap'规则打印'ves'的值。

checkCap :- writeln(ves(X,Y,Z)).

1 个解决方案

#1

Maybe this helps:

也许这有助于:

checkCap :-
    ves(X,Y,Z),          % look up dynamic database
    write(ves(X,Y,Z)),   % write out term
    nl.