RosettaCodeData/Task/Multisplit/Prolog/multisplit.pro

41 lines
974 B
Prolog

multisplit(_LSep, '') -->
{!},
[].
multisplit(LSep, T) -->
{next_sep(LSep, T, [], Token, Sep, T1)},
( {Token \= '' },[Token], {!}; []),
( {Sep \= '' },[Sep], {!}; []),
multisplit(LSep, T1).
next_sep([], T, Lst, Token, Sep, T1) :-
% if we can't find any separator, the game is over
( Lst = [] ->
Token = T, Sep = '', T1 = '';
% we sort the list to get nearest longest separator
predsort(my_sort, Lst, [(_,_, Sep)|_]),
atomic_list_concat([Token|_], Sep, T),
atom_concat(Token, Sep, Tmp),
atom_concat(Tmp, T1, T)).
next_sep([HSep|TSep], T, Lst, Token, Sep, T1) :-
sub_atom(T, Before, Len, _, HSep),
next_sep(TSep, T, [(Before, Len,HSep) | Lst], Token, Sep, T1).
next_sep([_HSep|TSep], T, Lst, Token, Sep, T1) :-
next_sep(TSep, T, Lst, Token, Sep, T1).
my_sort(<, (N1, _, _), (N2, _, _)) :-
N1 < N2.
my_sort(>, (N1, _, _), (N2, _, _)) :-
N1 > N2.
my_sort(>, (N, N1, _), (N, N2, _)) :-
N1 < N2.
my_sort(<, (N, N1, _), (N, N2, _)) :-
N1 > N2.