8-2

#! /usr/bin/env python3.2
# -*- coding: utf-8 -*-

# main.py
""" Task: Exercise 8.2
    Figure out which line of the above program is still not properly guarded.
    See if you can construct a text file which causes the program to fail and
    then modify the program so that the line is properly guarded and test it
    to make sure it handles your new text file.
"""

# test.txt is equal to mbox.txt, but added following 3 lines somewhere:
"""
>>> The next line fails with the original code:
From xyz
>>> because of there are more than one, but less than two words...
"""

''' Main '''
try:
    fhand = open('mbox.txt')
except:
    print("File not found!")
    exit()
week = ["Sat", "Sun", "Mon", "Tue", "Wed", "Fri"]
count = 0
for line in fhand:
    words = line.split()
    # print('Debug:', words)
    if len(words) <= 2: continue    # when there are less than 3 words
    if words[0] != 'From': continue
    if words[2] not in week[:]: continue
    try:                # Additional guard
        print(words[2])
        count += 1      # counts the interesting lines
    except IndexError:
        continue
print("There are " + str(count) + " interesting lines.")
try:
    fhand.close()
except:
    exit()