[Python-Dev] tally (and other accumulators)

Tue Apr 4 20:26:17 CEST 2006

[Alex] 
> This is quite general and simple at the same time: for example, it 
> was proposed originally to answer some complaint about any and all 
> giving no indication of the count of true/false items:
>> tally(bool(x) for x in seq)
>> would give a dict with two entries, counts of true and false items.

FWIW, sum() works nicely for counting true entries:
 >>> sum(x%3==0 for x in range(100))
 34
Raymond