Add a comment about the zip(*[zip(sorted(...),...)])

This commit is contained in:
Erik Johnston 2015-05-05 17:06:55 +01:00
parent bdcd7693c8
commit 9951542393

View file

@ -453,6 +453,14 @@ class SQLBaseStore(object):
if not values:
return
# This is a *slight* abomination to get a list of tuples of key names
# and a list of tuples of value names.
#
# i.e. [{"a": 1, "b": 2}, {"c": 3, "d": 4}]
# => [("a", "b",), ("c", "d",)] and [(1, 2,), (3, 4,)]
#
# The sort is to ensure that we don't rely on dictionary iteration
# order.
keys, vals = zip(*[
zip(
*(sorted(i.items(), key=lambda kv: kv[0]))