On 10/10/2013 2:45 AM, Chris Angelico wrote:
On Thu, Oct 10, 2013 at 5:12 PM, Peter Cacioppi
<peter.cacio...@gmail.com> wrote:
I'm trying to think of a good example usage of echo-argument and. Maybe
something like
A bit awkward, echo-argument or is more naturally useful to me then
echo-argument and.
first_element = some_list[0] # Oops, may crash
some_list[0:1] always works, and sometimes is usable, but you still
cannot index the slice.
try:
first_element = some_list[0]
except IndexError:
firstelement = None # A bit verbose
first_element = some_list and some_list[0]
# or if you want a zero instead of an empty list:
first_element = len(some_list) and some_list[0]
Also, consider the case where you have a function, or None:
result = func(*args,**kwargs) # NoneType is not callable
result = func and func(*args,**kwargs)
y = x and 1/x
One just has to remember that y==0 effectively means y==+-infinity ;-).
--
Terry Jan Reedy
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