On Thu, Mar 31, 2016 at 11:36 PM, Marko Rauhamaa <ma...@pacujo.net> wrote: > Chris Angelico <ros...@gmail.com>: > >> On Thu, Mar 31, 2016 at 10:22 PM, Antoon Pardon >> <antoon.par...@rece.vub.ac.be> wrote: >> Okay. I'll put a slightly different position: Prove that your proposal >> is worth discussing by actually giving us an example that we can >> discuss. > > Sorry for missing most of the arguments here, but if you are talking > about treating lists as special cases of dicts, I have occasionally > instinctively wanted something like this: > > >>> fields = [ "x", "y", "z" ] > >>> selector = (1, 1, 0) > >>> list(map(fields.get, selector)) > Traceback (most recent call last): > File "<stdin>", line 1, in <module> > AttributeError: 'list' object has no attribute 'get' > > Or course, I could: > > >>> list(map(fields.__getitem__, selector)) > ['y', 'y', 'x'] > > but that would abuse a dunder method. So I will need to: > > >>> list(map(lambda i: fields[i], selector)) > ['y', 'y', 'x'] > > or (most likely): > > >>> new_fields = [] > >>> for i in selector: > ... new_fields.append(fields[i]) > ... > >>> new_fields > ['y', 'y', 'x'] > > > This tiny problem of mine could be remedied by adding a get method to > lists.
Or, even more likely and even more Pythonic: >>> [fields[i] for i in selector] ['y', 'y', 'x'] As soon as you get past the easy and obvious case of an existing function, filter and map quickly fall behind comprehensions in utility and readability. ChrisA -- https://mail.python.org/mailman/listinfo/python-list
