All,
I have a dumb question...hopefully someone can shed some light on the
difference between for and while in the situation below.
I'm trying to iterate through a list I've created. The list consists
of a command, followed by a 'logging' message (a message printed to a
console or log file after the command is run).
Here's a small snippet of code:
# a list which includes (1) a command, and (2) something to be
dumped into a log file after the command runs
stuff = [ ["cat /etc/password"] , ["viewed /etc/password"] ]
#works
i = 0 ; j = 1
while i < len( stuff ):
os.system( str( stuff[ i ] ) )
print stuff[ j ]
i += 1 ; j += 1
The while loop does precisely what it should do: it runs the first
command using os.system(), and then prints out the string in the
second position of the list.
Then I tried to do the same thing with a for loop that looks
logically equivalent. I replaced the while loop with this for loop:
# doesn't work
for i in len( stuff ):
os.system( stuff[ i ] )
j = i + 1
print stuff[ j ]
Python doesn't like it, though. It gives me the following error:
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: 'int' object is not iterable
What precisely causes this error? I come from a C background, and
while and for loops can be molded to do precisely the same thing; it
doesn't seem like this is the case in this scenario.
Thoughts/ideas appreciated. :)
Thanks!
.james
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