Append commas between variables

Question

Following is my code. I want to append the ip:port string by a comma separated list.

ip = ['1.1.1.1', '2.2.2.2', '3.3.3.3', '4.4.4.4']
memcache = ''
port = '11211'
for node in ip:
    memcache += str(node) + ':' + port
    # join this by comma but exclude last one

I want output in this format:

memcache = 1.1.1.1:11211, 2.2.2.2:11211, 3.3.3.3:11211, 4.4.4.4:11211

How can I achieve that?

possible duplicate of [Concatenate elements of a list](http://stackoverflow.com/questions/16522362/concatenate-elements-of-a-list) — Felix Kling, Jan 30 '14 at 10:09

score 5 · Answer 1 · answered Jan 30 '14 at 10:08

5

memcache = ', '.join("{0}:{1}".format(ip_addr, port) for ip_addr in ip)

answered Jan 30 '14 at 10:08

Ewan

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You forgot the closing `"`. – gioi Jan 30 '14 at 10:08

score 4 · Answer 2 · answered Jan 30 '14 at 10:06

4

memcache = ', '.join(address + ':' + port for address in ip)

This uses the join method to join strings with ', ' as a separator. A generator expression is used to append the port to each address; this could also be done with a list comprehension. (There's actually no performance benefit to the genexp in this context, but I prefer the syntax anyway.)

answered Jan 30 '14 at 10:06

user2357112

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@AshwiniChaudhary: Indeed I did. – user2357112 Jan 30 '14 at 10:09

score 1 · Answer 3 · answered Jan 30 '14 at 10:09

1

memcache = ', '.join(address + ":" + port for address in ip)

best Peter

answered Jan 30 '14 at 10:09

Peter

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Append commas between variables

3 Answers3