[Tutor] I am terribly confused about "generators" and "iterators".. Help me

[Kent Johnson]

Bob Gailer wrote:
> Asrarahmed Kadri wrote:
>>  
>> What are generators and iterators...??And why are they are needed..??
>>  
>> I can do my stuff with a 'for' or a 'while' loop.. so why do I need an 
>> ITERATOR..?
> iterators & generators do not replace while or for loops! 

No, actually iterators and generators are the foundation of for loops. 
Whenever you write a for loop, Python creates an iterator to return the 
values that are assigned to the loop variables.

Writing your own iterator is a way to make a new kind of thing that can 
be iterated in a for loop. Generators are a convenient way to make 
iterators. They can be used to encapsulate loop logic. For some examples 
see these recent threads:
http://thread.gmane.org/gmane.comp.python.tutor/36068/focus=36069
http://article.gmane.org/gmane.comp.python.tutor/36105/match=generator

>>  
>> And what is a generator ..? I did try to read about these two things 
>> on the web, but still I AM CONFUSED.
> Well at risk of offering more web stuff, try 
> http://heather.cs.ucdavis.edu/~matloff/Python/PyIterGen.pdf

Thanks, that is very nice!

Kent

>> To HIM you shall return.
> I am glad that this thought brings you some comfort or stimulation. I 
> used to believe something similar, and all it did was bring me fear 
> guilt and shame.
> 
>