I have a small function that when passed a str that names a file that contains a program; it returns a 2-tuple with the number of the non-empty lines in that program, and the sum of the lengths of all those lines. Here is my current functioning code:

def code_metric(file_name):
    line_count = char_count = 0
    with open(file_name) as fin:
        stripped = (line.rstrip() for line in fin)
        for line_count, line in enumerate(filter(None, stripped), 1):
            char_count += len(line)
    return line_count, char_count

Is there a way to implement this function using functionals such as map, filter, and reduce and small lambdas to pass to these functionals? I could make it work conventionally but having some issue with using functionals. Any help would be great.

  • line_count can be obtained with len(lines) instead of an enumerate.
  • You use rstrip (rightstrip), I think that strip is better as you (probably) don't want to count the blanks of indentation as characters.
  • f is the standard name for files in Python not fin
  • Using list comprehension and a for loop as you do is much more readable than a functional alternative, anyway, down here I show you a functional version:


def code_metric(file_name):
    with open(file_name) as f:
        lines = f.read().splitlines()
    char_count = sum(map(len,(map(str.strip,filter(None,lines)))))
    return len(filter(None,lines)), char_count
  • \$\begingroup\$ @Caridorc- I tried using the function you gave but it keeps giving me the following error: char_count = sum(map(len, (map(str.strip(), filter(None, lines))))) TypeError: descriptor 'strip' of 'str' object needs an argument \$\endgroup\$ – LucyBen Feb 8 '15 at 19:42
  • \$\begingroup\$ @LucyBen excuse me, it is fixed now. \$\endgroup\$ – Caridorc Feb 8 '15 at 19:44
  • \$\begingroup\$ @Caridorc- Thank you. I've updated the question with your code. The output doesn't match when I ran as the figures are off. I've provided an example of the run as well. Hope that helps. \$\endgroup\$ – LucyBen Feb 8 '15 at 20:00
  • \$\begingroup\$ @Caridorc, you're counting un-filtered lines - essentially counting those that are empty too \$\endgroup\$ – volcano Feb 12 '15 at 23:08

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