def list_subscripting():
list_var = gen.str_gen.next()
element_name, seq_gen = \
random.choice([("element", gen.list_gen), ("character", gen.str_gen)])
a_list = gen.make_filter(lambda seq: len(seq) > 0)(seq_gen).next()
index = random.randrange(len(a_list))
position_func = random_position_func()
position = position_func(index, element_name)
message = "Let {var} = {value!r}. Select the {position} in {var}."
def question():
text = message.format(var=list_var, value=a_list, position=position)
show_text(text)
answer = raw_input(">>> ")
parsed_answer = ast.parse(answer)
list_name_correct = parsed_answer.body[0].value.value.id == list_var
list_index_correct = parsed_answer.body[0].value.slice.value.n == index
return list_name_correct and list_index_correct
return question
def list_subscripting():
list_var = gen.str_gen.next()
element_name, seq_gen = \
random.choice([("element", gen.list_gen), ("character", gen.str_gen)])
a_list = gen.make_filter(lambda seq: len(seq) > 0)(seq_gen).next()
index = random.randrange(len(a_list))
position_func = random_position_func()
position = position_func(index, element_name)
message = "Let {var} = {value!r}. Select the {position} in {var}."
def question():
text = message.format(var=list_var, value=a_list, position=position)
show_text(text)
answer = raw_input(">>> ")
parsed_answer = ast.parse(answer)
list_name_correct = parsed_answer.body[0].value.value.id == list_var
list_index_correct = parsed_answer.body[0].value.slice.value.n == index
return list_name_correct and list_index_correct
return question
def simple_slicing():
seq_var = gen.str_gen.next()
element_name, seq_gen = \
random.choice([("element", gen.list_gen), ("character", gen.str_gen)])
seq = gen.make_filter(lambda seq: len(seq) > 0)(seq_gen).next()
start_index = random.randrange(len(seq))
stop_index = random.randrange(start_index, len(seq)) + 1
template = "We have {var} = {value!r}. Select the range from the " \
"{start_pos} up to, but not including, the {end_pos}."
start_position = random_position_func()(start_index, element_name)
stop_position = random_position_func()(stop_index, element_name)
text = template.format(var=seq_var, value=seq, start_pos=start_position,
end_pos=stop_position)
def question():
show_text(text)
answer = raw_input(">>> ")
parsed_answer = ast.parse(answer)
parsed_expr = parsed_answer.body[0].value
seq_name_correct = parsed_expr.value.id == seq_var
slice_start_correct = parsed_expr.slice.lower.n == start_index
slice_stop_correct = parsed_expr.slice.upper.n == stop_index
return seq_name_correct and slice_start_correct and slice_stop_correct
return question
