From: Daryle Walker (darylew_at_[hidden])
Date: 2001-08-08 17:20:54
on 8/8/01 1:41 AM, John Max Skaller at skaller_at_[hidden] wrote:
> Daryle Walker wrote:
>> Looking at the (beginning of the) "(infinite) sequences using recurrence
>> relations" thread, I guess we need an iterating generator concept. It's a
>> generator with an iterator interface.
>> operator *() gets the current element, possibly from a cache
>> operator ++() goes to the next element
>> Optionally, operator --() could go to the previous element
> ?? But that is just the idea of an iterator in the first place.
> What am I missing?
I see an iterator as traversing over a container or a virtual container.
Generators in C++, with an operator()(), don't seem to be connected to a
container, but just create values. I sometimes want a generator to look
like an iterator. Now operator()() would "become" operator*() followed by
operator++(); the new-state returning functionality has been split up into
current-state returning and moving to the next state. Now I also have an
option of evaluating any previous states (bidirectional), at least by single
step. We could have the option of skipping several states (random access),
if it's efficient.
-- Daryle Walker Mac, Internet, and Video Game Junkie darylew AT mac DOT com
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