Re: Check for dict key existence, and modify it in one step.

On Tue, 2007-08-28 at 14:36 +0000, rodrigo wrote:
Im using this construct a lot:

if dict.has_key(whatever):
dict[whatever] += delta
else:
dict[whatever] = 1

In Python 2.5 there's a defaultdict class, otherwise you can subclass
dict like this:

class CountingDictionary(dict):
def increment(self, key, delta=1):
self[key] = self.get(key, 0) + delta

Hope this helps!

--
Evan Klitzke <evan@xxxxxxxx>

.

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