I am trying to check each index in an 8 digit binary string. If it is '0' then it is 'OFF' otherwise its 'ON'. I'm wondering if there's a more concise way to write this code with a switch-like feature.
Thanks,
I embedded a snippet from your very good link, roll it back if you don't like it.
Dustin Getz
2009-09-15 20:45:30
That doesn't have fall-through either.
dlamblin
2009-09-15 20:58:48
In *theory* you could implement a one-liner with fall-through by using defaultdict: >>> from collections import defaultdict >>> functions = defaultdict(lambda : not_found, a=function_1, b=function_2)but probably not a good idea in practice, particularly if the fall-through case is common :)
Ned Deily
2009-09-15 21:58:05
fall-through is a bad idea. good riddance.
joeforker
2009-09-16 01:35:24
+8
A:
No it doesn't. In the Python core language, one of the rules is to only have one way to do something. The switch is redundant to:
if x == 1:
pass
elif x == 5:
pass
elif x == 10:
pass
(without the fall-through, of course).
The switch was originally introduced to cut down on the number of angle brackets needed to do do similar if blocks, however, with python there are no brackets anyways.
Soviut
2009-09-15 20:48:50
Anyone who thinks Python "only has one way to do something" is very confused.
Glenn Maynard
2009-09-15 22:49:12
Fixed. I guess I could have claimed that it was python-esque pseudo-code, hehe.
Soviut
2009-09-15 22:49:39
@Glenn Maynard: There may be more than one way to do it, but "There should be one -- and preferably only one -- **obvious** way to do it", per PEP 20 ("The Zen of Python").
Daniel Pryden
2009-09-15 22:53:38
I believed `switch`'s purpose was to tell the compiler to build a jump table? (I know current compilers don't need this.)
Bastien Léonard
2009-09-15 22:54:29
@Glenn do understand that while there are many redundant python modules, the actual core language has little in the way of redundant functionality.
Soviut
2009-09-16 02:32:26
Although that way may not be obvious at first unless you're Dutch.
Stefano Borini
2009-09-16 13:09:46
+4
A:
Try this instead:
def on_function(*args, **kwargs):
# do something
def off_function(*args, **kwargs):
# do something
function_dict = { '0' : off_function, '1' : on_function }
for ch in binary_string:
function_dict[ch]()
Or you could use a list comprehension or generator expression if your functions return values:
result_list = [function_dict[ch]() for ch in binary_string]
Jeff
2009-09-15 20:50:47