mediawiki_dump_tools/Mediawiki-Utilities/mw/util/iteration/sequence.py

   1 from .peekable import Peekable
   2
   3
   4 def sequence(*iterables, by=None, compare=None):
   5     if compare is not None:
   6         compare = compare
   7     elif by is not None:
   8         compare = lambda i1, i2: by(i1) <= by(i2)
   9     else:
  10         compare = lambda i1, i2: i1 <= i2
  11
  12     iterables = [Peekable(it) for it in iterables]
  13
  14     done = False
  15     while not done:
  16
  17         next_i = None
  18
  19         for i, it in enumerate(iterables):
  20             if not it.empty():
  21                 if next_i is None or compare(it.peek(), iterables[next_i].peek()):
  22                     next_i = i
  23
  24         if next_i is None:
  25             done = True
  26         else:
  27             yield next(iterables[next_i])