extending file?

[Jeremy Jones]

Peter Hansen wrote:

> Chris Cioffi wrote:
>
>> Are there any docs or examples of extending the file type?  I work
>> with EDI messages that are very like text files, just with a few
>> quirks. ;-)  and I was wondering if I could strech and twist the built
>> in file type to make things a bit faster and more full featured.
>>
>> Specifically I would need to alter the iterator and ideally the line 
>> terminitor.
>
>
> It's unclear what you want to do.  Can you provide an example?
>
> Also consider whether you can achieve what you want merely
> by creating your own "file-like" object that wraps the
> standard file type.  This is the usual way to proceed.
>
> -Peter

I should really wait for the OP, but I've had too much caffeine this 
morning to just sit still.  An EDI message is a (fairly well) structured 
string of text (let's just say a file for now) that may consist of 
multiple interchanges, each interchange consisting of multiple segments 
(at least two, and each segment having a specific character denoting its 
end - all segments in an interchange will have the same segment 
terminator) and each segment consisting of multiple elements.  I believe 
the OP wants to be able to specify what character the file object will 
recognize as a line terminator (rather than the standard \n or \r\n), 
presumably so he can tell it that a segment terminator is the line 
terminator, do a readline(), and get an EDI segment instead of a 
"traditional" line of text.  Having dealt with EDI for nearly 6 years, I 
could see the benefit of this.  While I'm currently headed down the FSM 
route, it would be interesting to see the above mentioned alternative.

Jeremy Jones