Re: intuitive concept of iter

[muppet <scott asofyet org>]

On Feb 2, 2006, at 1:29 PM, zentara wrote:

> Can anyone explain what an "iter" is?

It's short for "iterator", and is a thing that is used as a handle to  
an item in a collection.  The idea is that using the iterator allows  
you to traverse the data structure without actually having to know or  
care about the actual details of the data structure.

Wikipedia says it much better than i:
http://en.wikipedia.org/wiki/Iterator

gtk+ uses iterators for the text and tree systems specifically to  
avoid the client program having to know the internals of those  
containers.  This allows any object to implement the TreeModel  
interface (just provide the iters, the actual storage is up to you),  
and allows handling utf-8 text with tags and possibly-embedded items  
in the TextBuffer without client code having to worry about the  
complexities of that storage.

You might argue that the perl bindings for gtk+ should try to hide  
the iterators from the perl developers.  You can get this sort of  
interface with Gtk2::Ex::Simple::TiedList and TiedTree.  We decided  
against making the tied interface the standard because there were  
some things that were just impractical to do efficiently through the  
ties, and there's always that feeling of "there's probably a better  
way."  For the TextView, i don't really know what a decent non-iter  
approach would be.



--
However, like all drugs, PANEXA can produce some notable side  
effects, all of which are probably really, really terrific and  
nothing that anyone should be concerned about, let alone notify any  
medical regulatory commission about.
  -- http://www.panexa.com