Reading a user-input string in prolog -


i beginner in prolog. using swi prolog(just started using it) , need split user input string list. tried following code, error stating 'full stop in clause-body?cannot redefine ,/2'

write('enter string'),nl,read('i'). tokenize("",[]). tokenize(i,[h|t]):-fronttoken(i,h,x),tokenize(x,t).

can me pls...

from error message, it's apparent you're using swi-prolog. can use library support:

?- read_line_to_codes(user_input,cs), atom_codes(a, cs), atomic_list_concat(l, ' ', a). |: hello world ! cs = [104, 101, 108, 108, 111, 32, 119, 111, 114|...], = 'hello world !', l = [hello, world, !].

to work more directly on 'strings' (really, string list of codes), i've built splitter, string//1 

:- use_module(library(dcg/basics)).  %%  splitter(+sep, -chunks) % %   split input on sep: minimal implementation % splitter(sep, [chunk|r]) -->     string(chunk),     (   sep -> !, splitter(sep, r)     ;   [], {r = []}     ).

being dcg, should called phrase/2

?- phrase(splitter(" ", strings), "hello world !"), maplist(atom_codes,atoms,strings). strings = [[72, 101, 108, 108, 111], [119, 111, 114, 108, 100], [33]], atoms = ['hello', world, !] .

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