Python: concatenate string and int in a loop

Question

I have a list of integers and I want to concatenate them in a loop.

This is what I have so far

a = [3, 4, 6]

temp = []
for i in a:
    query = 'Case:' + str(i)
    temp.append(query)

print(' OR '.join(temp))

>>> Case:3 OR Case:4 OR Case:6 

Is there a better way to write this?

Answer 1

Yes, you can use generator expression and str.join ,

' OR '.join('Case: {}'.format(i) for i in a)

Example/Demo -

>>> a = [3, 4, 6]
>>> ' OR '.join('Case: {}'.format(i) for i in a)
'Case: 3 OR Case: 4 OR Case: 6'

Answer 2

You can also use map and lambda expressions:

temp = map(lambda x: 'Case: '+str(x), a)

Answer 3

You could also use a comprehension:

>>> a = [3, 4, 6]
>>> ' OR '.join([ "Case " + str(x) for x in a ])
'Case 3 OR Case 4 OR Case 6'

Answer 4

完成@Joshua K使用map和lambda的想法（尽管我认为列表理解是一个更好的解决方案）：

>>> a = [3, 4, 6]
>>> 'OR '.join(map(lambda i: 'Case:' + str(i) + ' ', a))
Case:3 OR Case:4 OR Case:6