Tom Pinckney <[EMAIL PROTECTED]> added the comment: My latest need for something like this was something like this:
src1 = db_query(query_1) src2 = db_query(query_2) results = deduped(src1 + src2, key=lambda x: x.field2) Basically, I wanted data from src1 if it existed and otherwise from src2 , while preserving the order of src1 (I didn't care about order of src2). A previous example was reading from a file and wanting to de-dupe lines based on a field in each line. Again order mattered to me since I wanted to process the non-duped lines in the file in order. A final example was generating a bunch of error messages from a variety of sources and then wanting to make sure there were no duplicate errors. Instead of: errors = set(errors) I find this much clearer: errors = deduped(errors) In reality all of these examples probably do not need to be written as a generator. The lists being de-duped are probably not so huge in practice as to preclude instantiating a new list (given the reality of multi-gig RAM machines etc). It just seemed particularly clear to write this using a yield. An ordered dictionary would probably work for me too. I don't think a Bag would given it's lack of ordering. I do find it very simple to just be able to apply deduped() to any existing sequence/iterator and not have to be more verbose about explicitly iterating and filling in an ordered dictionary somehow. _______________________________________ Python tracker <[EMAIL PROTECTED]> <http://bugs.python.org/issue4615> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
