Pythonic way to join a string in a loop to create textblock

Question

Is there a pythonic way to join a string in a loop to create a block of text?

Example:

for x in range(4):
    content = f'{x}[block]'
    content+content

print(content)

Desired outcome:

0[block]
1[block]
2[block]
3[block]

Answer 1

You could use str.join() with a generator expression to join your block strings by newlines:

print("\n".join(f"{x}[block]" for x in range(4)))

Or for faster performance, use a list comprehension instead:

print("\n".join([f"{x}[block]" for x in range(4)]))

^{See this answer for more information on why the second approach is faster than the first}

Additionally, you could also append each block string to a list and join them at the end:

blocks = []
for x in range(4):
    blocks.append(f"{x}[block]")

print("\n".join(blocks))

If we want to simply print each block string without joining by newlines, we can make use of the sep keyword from print():

print(*(f"{x}[block]" for x in range(4)), sep="\n")

Output:

0[block]
1[block]
2[block]
3[block]