Easy function, please help.

rantingrick rantingrick at gmail.com
Wed Feb 9 15:51:25 CET 2011


On Feb 9, 1:08 am, Paul Rudin <paul.nos... at rudin.co.uk> wrote:
> Nanderson <mandersonrandersonander... at gmail.com> writes:
> > loop would be infinite. I get what is happening in the function, and I
> > understand why this would work, but for some reason it's confusing me
> > as to how it is exiting the loop after a certain number of times. Help
> > is appreciated, thanks.
>
> It works because 0 tests false and because integer division yields
> integers... eventually you'll get something like 1/10 giving 0.

It works because of a design flaw in the language! Specifically i am
referring to treating the integer 0 as False and any other integers as
True. There is also the empty vs non empty containers that work this
way besides numeric types.

----------------------------------
 Python 3.1.1 Interactive Session
----------------------------------
>>> bool(0)
False
>>> bool(1)
True
>>> bool(-1)
True
>>> bool(-1.0)
True
>>> bool(1.0)
True
>>> bool(0.0)
False
>>> bool([])
False
>>> bool([1])
True

Sure it *seems* like a "bright" idea at first however later you find
out this sort of laziness just induces more subtle bugs in code.
Python3000 fixed a lot of warts in Python2.x HOWEVER, python3000 did
not go near far enough! We need more radical changes (and when i say
radical i mean removing poorly thought out design patterns like this
"boolean emulation"!) to the language before python will be a truly
21st century language.

We should have never written code like this...

------------
 Example 1:
------------
# lst = []

if lst:
    blah
if not lst:
    blah

Example 1 is not explicit enough. Too much guessing is required by the
reader!

-----------
 Example 2
-----------
if lst.lengh > 0:
    blah
if not lst.empty():
    blah
if not empty(lst):
    blah

Example 2 is just explicit enough so that the reader knows *exactly*
what is happening! We don't want to be redundantly explicit, however
we sure as *hell* don't want to be implicit! Hmm, believe i read that
somewhere once... import this!

The point is NEVER use an integer in place of a boolean! And i am NOT
blaming the OP here, no! I am blaming who ever came up with this
idiotic "emulation of booleans" crap! And don't tell me... "Well C did
it first we were just following by example"... because you just make
yourself out to be even a bigger idiot!

Here is another example of bad habits passed down from "on high".

def is_foo():
    if something:
        return 1
    return 0

Why the HELL are you retuning integers in an obviously boolean
function? Are you trying to win Pearl hacker of the year award? Please
folks, always remember... NEVER emulate booleans, always use True/
False for boolean behaviors.

def is_foo():
    if something:
        return True
    return False

*school-bell*



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