Does anyone else use this little idiom?

[Steve Holden]

Jeff Schwab wrote:
> How miller.paul.w at gmail.com wrote:
>> Ruby has a neat little convenience when writing loops where you don't
>> care about the loop index: you just do n.times do { ... some
>> code ... } where n is an integer representing how many times you want
>> to execute "some code."
>>
>> In Python, the direct translation of this is a for loop.  When the
>> index doesn't matter to me, I tend to write it as:
>>
>> for _ in xrange (1,n):
>>    some code
>>
>> An alternative way of indicating that you don't care about the loop
>> index would be
>>
>> for dummy in xrange (1,n):
>>    some code
>>
>> But I like using _ because it's only 1 character and communicates well
>> the idea "I don't care about this variable."
>>
>> The only potential disadvantages I can see are threefold:
>>
>> 1. It might be a little jarring to people not used to it.  I do admit
>> it looks pretty strange at first.
>>
>> 2. The variable _ has special meaning at the interactive interpreter
>> prompt.  There may be some confusion because of this.
>>
>> 5.  Five is right out.  (ob Holy Grail reference, of course. :-)
>>
>> So, I guess I'm wondering if anyone else uses a similar idiom and if
>> there are any downsides to it that I'm not aw
> 
> Would something like this be acceptable?  It still requires a loop 
> variable, plus an extra line of code per loop, plus a one-time class 
> definition (and import into each client module), and it's probably 
> slower than "for dummy in range."  The syntax might be more inuitive 
> than "dummy" or "_" in a for loop, though.
> 
> class Go:
>      def __init__(self, count):
>          self.count = count
> 
>      def again(self):
>          if self.count <= 0:
>              return False
>          self.count -= 1
>          return True
> 
> go = Go(3)
> while go.again():
>      print "hello"

One could rename the again() method __call__(), allowing the even more 
horrible but less verbose

while Go(3)():
     print "hello"

That'd confuse the newbies!

regards
  Steve
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