Denis Bilenko wrote: > Why does list have no 'get' method with exactly the same semantics as > dict's get, > that is "return an element if there is one, but do NOT raise > an exception if there is not.": > > def get(self, item, default = None): > try: > return self[item] > except IndexError: > return default > > It is often desirable, for example, when one uses the easiest > command-line options parsing - based on absolute positions:
Dodging your question slightly (and at the risk of teaching my grandmother to suck eggs) I sometimes use this idiom for checking params. Obviously it only goes so far, but it's fairly compact: <Noddy example code> import os, sys if __name__ == '__main__': ARGS = None, "DEV" filename, db = \ (j or i for i, j in map (None, ARGS, sys.argv[1:])) print sys.argv print filename, db </code> TJG -- http://mail.python.org/mailman/listinfo/python-list