Question

What would be your preferred way to concatenate strings from a sequence such that between every two consecutive pairs a comma is added. That is, how do you map, for instance, ['a', 'b', 'c'] to 'a,b,c'? (The cases ['s'] and [] should be mapped to 's' and '', respectively.)

I usually end up using something like ''.join(map(lambda x: x+',',l))[:-1], but also feeling somewhat unsatisfied.

Answer 1

my_list = ['a', 'b', 'c', 'd'] my_string = ','.join(my_list) 

'a,b,c,d' 

This won’t work if the list contains integers

---

And if the list contains non-string types (such as integers, floats, bools, None) then do:

my_string = ','.join(map(str, my_list))