AttributeError when taking result of counter, but not with a plain integer

Question

I'm attempting to use the code below to get the total number of lines in a text file.

totallines = 0
for line in infile:
    totallines += 1

It works, and can print the correct number to the shell. However, when I assign the result to:

item = [0]*totallines

I get an AttributeError when forcing the given line into lowercase with:

item[i] = item[i].lower()

Yet, if I remove the line counter, and replace it with the number of lines in the text file. It works perfectly.

How can I fix this?

Answer 1

It sounds like you'd like to convert the lines of the input file to lowercase and store the result in an array. You could do it this way:

with open('myfile.txt', 'r') as infile:
    items = [line.lower() for line in infile]

Or (somewhat) equivalently, (This one drops the "\n" at the end of each line):

with open('myfile.txt', 'r') as infile:
    items = infile.read().lower().splitlines()

Note: Don't use file as a variable name, since it overshadows the builtin file type.