How would you code a program in Prolog to print numbers from 1 to 10 using recursion?

How would you code a program in Prolog to print numbers from 1 to 10 using recursion?

I've tried the following but it doesn't work, can you tell me why?

print_numbers(10) :- write(10).

print_numbers(X) :- write(X),开发者_如何学编程nl,X is X + 1, print_numbers(X).

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Your code is very close to working. The problem is that you cannot reuse X, once it is instantiated, it cannot be changed (see here for more details). Use a new variable, like this:

print_numbers(10) :- write(10), !.
print_numbers(X) :- write(X), nl, Next is X + 1, print_numbers(Next).

Adding the cut (!) to the end will prevent the interpreter from asking if you want to see more results.

?- print_numbers(1).
1
2
3
4
5
6
7
8
9
10

Yes
?- 

---

print_from_1_to_10 :-
        print_from_X_to_10(1).

print_from_X_to_10(X) :-
        (
                X > 10
        ->
                fail
        ;
                writeln(X),
                NewX is X + 1,
                print_from_X_to_10(NewX)
        ).

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Been a seriously long time since I wrote any prolog but I'd probably do things just a little differently. Something like this, though I can't test it at the momment.

print_increasing_numbers(From, To):- From > To, !, write('ERROR: From > To').

print_increasing_numbers(To, To):- !, write(To).

print_increasing_numbers(From, To):- write(From),
                                     nl,
                                     Next is From + 1,
                                     print_increasing_numbers(Next, To).

A key difference here is the !, or cut operation, which stops backtracking. If you don't include it then you will get a solution with the first clause when X is 10,but if you ask for a second solution it will backtrack and match the second clause as well. That would result in a much larger list of numbers than you want.

---

Just call defineXandY from terminal

defineXandY :-
    print_one_to_ten(1,10).

print_one_to_ten(X,Y) :- 
    X<Y,
    write(X),nl,
    NewX is X+1,
    print_one_to_ten(NewX,Y).