On Sun, Apr 19, 2009 at 2:06 AM, Nick Coghlan <ncogh...@gmail.com> wrote: > That said, I'm starting to wonder if an even better option may be to > just drop the kwargs support from the function and require people to > always supply a parameters dictionary. That would simplify the signature > to the quite straightforward: > > def add_query_params(url, params, allow_dups=True, sep='&')
That's the most straightforward and I like this more than the one below. > I agree that isn't a good option, but mapping True/False/None to those > specific behaviours also seems rather arbitrary (specifically, it is > difficult to remember which of "allow_dups=False" and "allow_dups=None" > means to ignore any duplicate keys and which means to ignore only > duplicate items). I'd say it's less of a problem when using named arguments, i.e. you read it as: allow_dups=True : yes allow_dups=False : effeminately no :), allow_dups=None : strictly no which more or less corresponds to the behaviour. > It also doesn't provide a clear mechanism for > extension (e.g. what if someone wanted duplicate params to trigger an > exception?) > > Perhaps the extra argument should just be a key/value pair filtering > function, and we provide functions for the three existing behaviours > (i.e. allow_duplicates(), ignore_duplicate_keys(), > ignore_duplicate_items()) in the urllib.parse module. This would be the most flexible and conceptually right (ye olde strategy pattern), but would clutter the API. > Note that your implementation and docstring currently conflict with each > other - the docstring says "pass them via a dictionary in second > argument:" but the dictionary is currently the third argument (the > docstring also later refers to passing OrderedDictionary as the second > argument). It's a mistake that exemplifies once again that positional args are awkward :). --- So, gentlemen, either def add_query_params(url, params, allow_dups=True, sep='&') or def allow_duplicates(...) def remove_duplicate_values(...) ... def add_query_params(url, params, strategy=allow_duplicates, sep='&') _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
