prolog - How to loop through a list to create a specific other list -

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i need define predicate parses given list looks following:

change([10,-,6], list). //send list = [item(num, 10), item(minus, _), item(num, 6)] //returns this.

i have no idea how check if item in list 'num', or if minus or what...

change([], _). change([h|rest], list) :- "do atom here?" , transform(rest, [item(atom, h) | list] ).

what might like?

since you're applying transformation on each list' element, change/2 should be

change([], []).  change([h|rest], [q|list]) :- qualify(h,q) change(rest, list]).

and

qualify(n, item(num, n)) :- number(n), !. qualify(-, item(minus, _)) :- !. qualify(a, item(atom, a)).  % left unspecified, assume else atom...

the change/2 it's maplist, , written as:

change(i, o) :- maplist(qualify, i, o).

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