Have csv.reader tell when it is on the last line

Question

Apparently some csv output implementation somewhere truncates field separators from the right on the last row and only the last row in the file when the fields are null.

Answer 1

I am aware it is an old question, but I came up with a different answer than the ones presented. The reader object already increments the line_num attribute as you iterate through it. Then I get the total number of lines at first using row_count, then I compare it with the line_num.

import csv

def row_count(filename):
    with open(filename) as in_file:
        return sum(1 for _ in in_file)

in_filename = 'somefile.csv'
reader = csv.reader(open(in_filename), delimiter='|')

last_line_number = row_count(in_filename)
for row in reader:
    if last_line_number == reader.line_num:
        print "It is the last line: %s" % row