diff options
Diffstat (limited to 'prolog/problems/lists/permute_2/common.py')
| -rw-r--r-- | prolog/problems/lists/permute_2/common.py | 77 |
1 files changed, 76 insertions, 1 deletions
diff --git a/prolog/problems/lists/permute_2/common.py b/prolog/problems/lists/permute_2/common.py index e39300b..3035159 100644 --- a/prolog/problems/lists/permute_2/common.py +++ b/prolog/problems/lists/permute_2/common.py @@ -2,6 +2,9 @@ from operator import itemgetter import prolog.engine +import prolog.util +import socket +from server.hints import Hint, HintPopup import server.problems id = 107 @@ -19,6 +22,19 @@ permute(L, [X|P]) :- permute(L1, P). ''' +hint_type = { + 'eq_instead_of_equ_markup': HintPopup('eq_instead_of_equ_markup'), + 'eq_instead_of_equ': Hint('eq_instead_of_equ'), + 'predicate_always_false': Hint('predicate_always_false'), + 'base_case': Hint('base_case'), + 'recursive_case': Hint('recursive_case'), + 'timeout': Hint('timeout'), + 'base_case_arbitrary': Hint('base_case_arbitrary'), + 'second_base_case_missing': Hint('second_base_case_missing'), + 'unsuccessful_conc_use': Hint('unsuccessful_conc_use'), + 'forcing_result_onto_recursion': Hint('forcing_result_onto_recursion'), +} + test_cases = [ ('permute([], X)', [{'X': '[]'}]), @@ -48,5 +64,64 @@ def test(code, aux_code): return n_correct, len(test_cases), hints def hint(code, aux_code): - # TODO + tokens = prolog.util.tokenize(code) + + try: + engine_id, output = prolog.engine.create(code=code+aux_code, timeout=1.0) + + # strict equality testing instead of simple matching + # this is usually (but not necessarily) wrong + targets = [prolog.util.Token('EQ', '==')] + marks = [(t.pos, t.pos + len(t.val)) for t in tokens if t in targets] + if marks: + return [{'id': 'eq_instead_of_equ_markup', 'start': m[0], 'end': m[1]} for m in marks] + \ + [{'id': 'eq_instead_of_equ'}] + + # general unsuccessful use of conc (not appropriate for this exercise) + if prolog.util.Token('NAME', 'conc') in tokens: + return [{'id': 'unsuccessful_conc_use'}] + + # recursion is getting bigger and bigger + + + # forcing result onto recursion; case of divide(T, [H1|L1], [H2|L2]) + if not prolog.engine.ask_truthTO(engine_id, 'divide([a,b,c], _, _)') and \ + prolog.engine.ask_truthTO(engine_id, + 'asserta( divide([cob], [yowza,cob], [brix]) ), divide([yowza,brix,cob], [cob], []), retract( divide([cob], [yowza,cob], [brix]) )'): + return [{'id': 'forcing_result_onto_recursion'}] + + # base case succeeds with arbitrary result + if prolog.engine.ask_truthTO(engine_id, 'divide([], L1, L2), (var(L1) ; var(L2))') or \ + prolog.engine.ask_truthTO(engine_id, 'divide([q], L1, L2), (var(L1) ; var(L2))') or \ + prolog.engine.ask_truthTO(engine_id, 'divide([q], [q|L1], L2), (var(L1) ; var(L2))'): + return [{'id': 'base_case_arbitrary'}] + + # one base case ok, the other one is missing (or bad) + # only trigger when recursion also works, because that makes more sense to the student + # than immediately telling him or her that there is another base case missing + if prolog.engine.ask_truthTO(engine_id, + 'divide([a,b], [a], [b]), \+ divide([a,b,c], [a,c], [b]) ; \+ divide([a,b], [a], [b]), divide([a,b,c], [a,c], [b])'): + return [{'id': 'second_base_case_missing'}] + + # missing/failed base case + if not prolog.engine.ask_truth(engine_id, 'divide([], [], [])'): + return [{'id': 'base_case'}] + +# # target predicate seems to always be false +# if not prolog.engine.ask_truthTO(engine_id, 'divide([_,_,_,_,_], _, _)') and \ +# not prolog.engine.ask_truthTO(engine_id, 'divide([_,_,_,_,_,_], _, _)'): +# return [{'id': 'predicate_always_false'}] + + # base cases work, the recursive doesn't (but it doesn't timeout) + # this may be left as the last, most generic hint + if not prolog.engine.ask_truth(engine_id, 'divide([qa,qb,qc,qd], [qa,qc], [qb,qd])'): + return [{'id': 'recursive_case'}] + + except socket.timeout as ex: + return [{'id': 'timeout'}] + + finally: + if engine_id: + prolog.engine.destroy(engine_id) + return [] |