John J. Lee writes: "the patch makes it possible to implement
functionality like HTTP cookie handling, Refresh handling,
etc. etc. using handler objects. At the moment urllib2's handler
objects aren't quite up to the job, which results in a lot of
cut-n-paste and subclassing. I believe the changes are
backwards-compatible, with the exception of people who've
reimplemented build_opener()'s functionality -- those people would
need to call opener.add_handler(HTTPErrorProcessor).
The main change is allowing handlers to implement
methods like:
http_request(request)
http_response(request, response)
In addition to the usual
http_open(request)
http_error{_*}(...)
"
Note that the change isn't well documented at least in part because
handlers aren't well documented at all. Need to fix this.
Add a bunch of new tests. It appears that none of these tests
actually use the network, so they don't need to be guarded by a
resource flag.
* show that it is typically used with sorted data,
* highlight commonalities with SQL's groupby and Unix's uniq,
* demonstrate valid uses for the default identity function,
* add some excitement by suggesting the range of possibilities.
The example code did not work and could not easily be made to work.
Since the docs were already complex and the feature was not used
(it took two years for the errors to surface), we decided to dedocument
it entirely, leaving unittest cleaner than before.
Original idea by Guido van Rossum.
Idea for skipable inner iterators by Raymond Hettinger.
Idea for argument order and identity function default by Alex Martelli.
Implementation by Hye-Shik Chang (with tweaks by Raymond Hettinger).
and left shifts. (Thanks to Kalle Svensson for SF patch 849227.)
This addresses most of the remaining semantic changes promised by
PEP 237, except for repr() of a long, which still shows the trailing
'L'. The PEP appears to promise warnings for operations that
changed semantics compared to Python 2.3, but this is not
implemented; we've suffered through enough warnings related to
hex/oct literals and I think it's best to be silent now.