Thomas Nelson wrote:
> I have this code:
> type1 = [0]
> type2 = [0]
> type3 = [0]
> map = {0:type1, 1:type1, 2:type3, 3:type1, 4:type2}
Warning : you're shadowing the builtin map() function.
> # the real map is
> longer than this
>
> def increment(value):
> map[value][0] += 1
>
> increment(1)
> increment(1)
> increment(0)
> increment(4)
> #increment will actually be called many times through other functions
> print type1[0], type2[0], type3[0]
> #should print "3 1 0"
>
> This is exactly what I want to do: every time I encounter this kind of
> value in my code, increment the appropriate type by one. Then I'd like
> to go back and find out how many of each type there were. This way
> I've written seems simple enough and effective, but it's very ugly and
> I don't think it's the intended use of lists.
Not really.
> Does anyone know a
> cleaner way to have the same funtionality?
# first replace the list hack
class Counter(object):
def __init__(self, name, *keys):
self.name = name
self.keys = keys
self.count = 0
def inc(self):
self.count += 1
# now wrap the whole thing in a convenient way
class Counters(object):
def __init__(self, *counters):
self._counters = dict()
self._counters_map = dict()
for counter in counters:
assert counter.name not in self._counters
self._counters[counter.name] = counter
for key in counter.keys:
assert key not in self._counters_map
self._counters_map[key] = counter
def __getattr__(self, name):
return self._counters[name].count
def __getitem__(self, key):
return self._counters_map[key].count
def __call__(self, key):
self._counters_map[key].inc()
# and finally, let's use it:
increment = Counters(Counter("type1", 0, 1, 3),
Counter("type2", 4),
Counter("type3", 2)
)
increment(1)
increment(1)
increment(0)
increment(4)
print increment.type1, increment.type2, increment.type3
HTH
--
bruno desthuilliers
python -c "print '@'.join(['.'.join([w[::-1] for w in p.split('.')]) for
p in '[EMAIL PROTECTED]'.split('@')])"
--
http://mail.python.org/mailman/listinfo/python-list
