Question

I am having a list as :

>>> l = ['1', '2', '3', '4']

if I use join statement,

>>> s = ', '.join(l)

will give me output as :

'1, 2, 3, 4'

But, what I have to do If I want output as :

'1, 2, 3, 4,'

(I know that I can use string concat but I want to know some better way)

.

Answer 1

String concatenation is the best way:

l = ['1', '2', '3', '4']  # original list
s = ', '.join(l) + ','

but you have other options also:

1. Mapping to comma-ended strings, then joining:

   l = ['1', '2', '3', '4']  # original list
   s = ' '.join(map(lambda x: '%s,' % x, l))
   

2. Appending empty string to the joined list (don’t modify original l list!):

   l = ['1', '2', '3', '4']  # original list
   s = ', '.join(l + ['']).rstrip(' ')
   

3. Using string formatting in place of concatenation:

   l = ['1', '2', '3', '4']  # original list
   s = '%s,' % (', '.join(l))