python - 为什么是string.join（list）而不是list.join（string）？(Why is it string.join(list) instead of list.join(string)?)

Question

This has always confused me.

(这一直使我感到困惑。)

It seems like this would be nicer:

(看起来这样会更好：)

my_list = ["Hello", "world"]
print(my_list.join("-"))
# Produce: "Hello-world"

Than this:

(比这个：)

my_list = ["Hello", "world"]
print("-".join(my_list))
# Produce: "Hello-world"

Is there a specific reason it is like this?

(是否有特定原因？)

  ask by Evan Fosmark translate from so

Answer 1

It's because any iterable can be joined, not just lists, but the result and the "joiner" are always strings.

(这是因为任何iterable都可以联接，不仅是列表，而且结果和“ joiner”始终是字符串。)

For example:

(例如：)

import urllib2
print('
############
'.join(
    urllib2.urlopen('http://data.stackexchange.com/users/7095')))