david pokorny vpwtpanfhgmailcom tue apr 1 2008 737 pm martin v löwis wrote think fairly obvious 2x keys change wasteful actually build list keys dictionary even values create tuples well want iterate common operation keys iterate look right agree common operationscenario one describe dont understand behavior common name efficient implementation common scenario one could propose alternate policy behavior common name correspond common human interpretation name according policy think valid arguments made keys return either list set set never used python 2 list dont think dict_keys object tied underlying dict common interpretation meaning keys outside list good policy minimizes mental housekeeping required understand given piece code real benefit programmer especially programmer coming python due respect policy describea efficient implementation common caseoptimizes code people dont think issue words facilitates premature optimization david _______________________________________________ python3000 mailing list smsbmo9552pythonorg httpmailpythonorgmailmanlistinfopython3000 unsubscribe httpmailpythonorgmailmanoptionspython3000python300040tangomucom wed 06 aug 2008 220829 0700 python3000 spooky behavior dictitems friends