Python for-loop without index and item
Question:
Is it possible in python to have a for-loop without index and item?
I have something like the following:
list_1 = []
for i in range(5):
list_1.append(3)
The code above works fine, but is not nice according to the pep8 coding guidelines.
It says: “Unused variable ‘i'”.
Is there a way to make a for-loop (no while-loop) without having neither the index nor the item? Or should I ignore the coding guidelines?
Answers:
You can replace i with _ to make it an ‘invisible’ variable.
See related: What is the purpose of the single underscore "_" variable in Python?.
While @toine is completly right about using _, you could also refine this by means of a list comprehension:
list_1 = [3 for _ in range(5)]
This avoids the ITM ("initialize, than modify") anti-pattern.
Is it possible in python to have a for-loop without index and item?
I have something like the following:
list_1 = []
for i in range(5):
list_1.append(3)
The code above works fine, but is not nice according to the pep8 coding guidelines.
It says: “Unused variable ‘i'”.
Is there a way to make a for-loop (no while-loop) without having neither the index nor the item? Or should I ignore the coding guidelines?
You can replace i with _ to make it an ‘invisible’ variable.
See related: What is the purpose of the single underscore "_" variable in Python?.
While @toine is completly right about using _, you could also refine this by means of a list comprehension:
list_1 = [3 for _ in range(5)]
This avoids the ITM ("initialize, than modify") anti-pattern.