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prologimmutability

Prolog - Manipulating the same list for several times

I am new to Prolog and trying to modify a list by deleting elements by indices.

For example:

remove(1,[1,2,3],Z).  
Z is [1,3].

However, when I try to run this predicate again, the list is sent as [1,2,3].

As far I searched, I think it cant be implemented in Prolog Is that true ?

And if its true, what alternatives I can try ?

I have been stuck in it for a long time and really any help is appreciated.

Solution

  • Using the predefined predicates nth0/3 and select/3

    ?- nth0(1,[1,2,3],Element),select(Element,[1,2,3],Z).
Element = 2,
Z = [1, 3] ;
false.