I want to freeze my goal until some variable, for example list, is unbounded, right now I have

```
sieve(N,L) :-
freeze(Aux,sieve(N,L,[],Aux)),
numlist(2,N,Aux).
sieve(N,L,R,[H|T]) :-
freeze(X, X mod H =\= 0 ; X == H),
findall(X,select(X,T,_),P),
sieve(N,L,[H|R],P).
sieve(_,L,L,[]).
```

But it stop after some operations and waits forever. Could someone tell me how to correct this?

# Best How To :

Ok i found out solution i had to change recursive call in `sieve`

so now i call it in freeze predicate.

as requested i found clue here Lazy lists in Prolog?

```
sieve(N,L) :-
sieve(L,Strumien,[]),
numlist(2,N,X),
X = Strumien.
sieve(L,Strumien,X) :-
freeze(Strumien,
( Strumien =[H|T],
filter(H,T,Z),
sieve(L,Z,[H|X])
)).
sieve(L,[],L).
filter(H,S,X) :-
filter(H,S,X,[]).
filter(_,[],X,X).
filter(H,S,X,Y) :-
freeze(S,S =[H1|T]),
( H1 mod H =\= 0 ->
append(Y,[H1],Y2),
filter(H,T,X,Y2)
;
filter(H,T,X,Y)
).
```