Mailman 3 Function to return first(or last) true value from list - Python-ideas

18 Feb 2014

      It isn't uncommon to try and get either the first or the last True value
from a list. In Python 2, you'd do this:

next((x for x in mylist if x))

And, in Python 3, thanks to filter returning an iterator, you'd do this:

next(filter(bool,mylist))

It still is pretty common. Common enough to make it aggravating to write a
function to do that nearly every time. My idea is to add first and
lastfunctions that do just that.

Stuff that's open to lots of debate:

   -

   Names. They're not very creative; I know.
    -

   Builtin or itertools. I'm personally leaning towards the latter at the
   moment.

Implementing it in itertools would be simple:

def first(it):
    return next(filter(bool,it))
def last(it):
    return next(reversed(filter(bool,it)))

-- 
Ryan
If anybody ever asks me why I prefer C++ to C, my answer will be simple:
"It's becauseslejfp23(@#Q*(E*EIdc-SEGFAULT. Wait, I don't think that was
nul-terminated."

Function to return first(or last) true value from list

Ryan Gonzalez

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