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listsplitprologdcg

Split words from string in Prolog

I want to split words from string and put into a list in Prolog.

num --> [one] | [two] | [three] | [four] | [five].

?- split("onethreetwofive", Ls).
Ls = [one,three,two,five].             % expected answer

Here, I want to split the string with matching list from num and put the words in list. I am using SWI-Prolog. Any ideas? Thanks!

Solution

  • Lets try this code.
    :-set_prolog_flag(double_quotes, codes).
    any(A,K) --> {member(S,K)}, S, {atom_codes(A, S)}.
    num(S) --> any(S, ["one","two","three","four","five"]).
    nums([]) --> "".
    nums([X|Xs]) --> num(X), nums(Xs).

    split(Str,Ls):-phrase(nums(Ls),Str).

    Ok Now Let's run the query.
    ?- split("onethreetwofive", Ls).
    Ls = [one, three, two, five] ;