any() and all() on empty list?

[Piet van Oostrum]

>>>>> "Steve R. Hastings" <steve at hastings.org> (SRH) wrote:
[snip]
>SRH> vowels = frozenset("aeiouAEIOU")
>SRH> f = open("a_file.txt")  # note that f is an iterator

>SRH> counts = tally(line[0] in vowels for line in f)

tally([line[0] in vowels for line in f])

>SRH> # counts is a dict; counts.keys() == [False, True]

No guarantee about the order. It could be [True, False]. 

>SRH> count_nonvowels, count_vowels = counts.values()

So you must use counts[False] and counts[True].

-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://www.cs.uu.nl/~piet [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org