[Python-Dev] lifting of prohibition against readlines inside a "for line in file" in Py3?

[Mitchell L Model]

In Digest Vol. 67, Issue 52 (13 Feb 2009) I pointed out that Python 
2's prohibition against performing readlines on a file being iterated 
over appears to have been lifted in Python 3. I asked if this was 
intentional and whether it should be add to the "What's New" 
documentation.  I also expressed muy surprise that "for line in 
fil"'s can be nested using the same fil in both Python 2 and 3. I 
presented an example for each point and some and further comments.

I didn't get any response. Is this the wrong list for the question? 
Did appropriate responders assume another would respond? I want to 
reraise this because lifting of that prohibition is a quite 
significant change in the behavior from Python 2. Even if it ws a bug 
in Python 2, or the side effect of other changes in Python 3, it 
should at least be documented prominently. True, no-one's code will 
be affected by lifting a prohibition against something their code 
couldn't have done, but the new behavior offers significant 
flexibility in writing "for line in fil" iterations in that it allows 
recognizing the beginning of a sequence of lines that should be 
considered a unified "chunk" and allows the loop to do readlines to 
handle the rest of the chunk. Some of these can be handled by just 
nesting a second "for line in fil" inside a conditional inside the 
outer iteration but some are better handled by individual readlines.

I'd appreciate comments -- especially a redirection to a different 
list, if this one isn't appropriate for my query.