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Comment by kstrauser | Hacker News Reader

There's not a great `reduce` replacement with comprehensions. It'd probably be something closer to:

  last = initial
  for value in iter:
      last = byfun(last, value)

However, I don't find myself writing that frequently.

You forgot the walrus operator!

  accum = initial
  series = [accum := bifun(accum, value) for value in seq]
  # result = series[-1]

To be honest, this is the first time I've used the walrus operator.

All hail the walrus!

(Seriously, I like that.)

This is very nice. Replaces reduce() for me. Now to upgrade to Python 3.8! (stock Python on my cloud machine is still 3.7)

doesn't it use a lot of memory since we're only interested in the last value?

You can do the same thing with a generator.

    x = 0
    deque((x := x + 1 for _ in range(10)), maxlen=0)
    print(x)
    >> 10

Using deque to consume generators is an old trick documented in the itertools recipes: https://docs.python.org/3/library/itertools.html#itertools-r...