Nathan Pinno said unto the world upon 08/07/2005 16:14:
> Thanks, Danny and all.
>
> Adjusted the code, here is the newest code and error:
<snip>
> def add_login_command(site,filename):
> print "Add a login info card"
> site = raw_input("Site: ")
> id = raw_input("User ID: ")
> passcard = raw_input("Password: ")
> sitelist[site] = [id,passcard]
<snip>
> while menu_choice != "9":
> menu_choice = raw_input("Choose an option: ")
> if menu_choice == "1":
> add_login_command()
<snip>
> Error Message:
> Traceback (most recent call last):
> File "D:\password.py", line 73, in ?
> add_login_command()
> TypeError: add_login_command() takes exactly 2 arguments (0 given)
>
> How do I fix it so that it runs properly, and any other errors that have
> to be fixed?
Hi Nathan,
(Having just finished this long email up, I see that Danny is quicker,
terser, and more to the point than I am. But I hate to waste the
effort, so I'm sending anyway. In case of conflict, go with what Danny
said :-)
First, I mean what I am about to say as a constructive comment.
It seems like you have been getting an error message and then posting
the error msg and entire generating code to the list. It is good you
are giving the exact error msg now, but posting the entire code isn't
really the best idea. It would be much better if you instead tried to
post a smaller chunk of the code that still exhibits the behaviour
you'd like help with. (My snips don't leave it running but that is the
general idea.)
This is good for 2 reasons:
1) It makes it less time-consuming for those who want to help you,
and
2) It is a great way of helping yourself. Trimming things down is a
valuable way for you to gain general understanding *and* will often
result in your determining the answer to your own question.
No one on the list minds helping, that's what its for (and goodness
knows, I'm grateful for the hours and hours of effort list members
have put into helping me). But, the ultimate point is to learn to help
yourself, right? :-)
So, to your particular problem:
Look at the code that remains above. The error msg is complaining that
the function add_login_command takes 2 arguments and that it was
called with none. And sure enough, if you look at your def block for
the function:
def add_login_command(site,filename):
# code goes here
and the block causing the error:
if menu_choice == "1":
add_login_command()
you've called it with no arguments at all. Hence the poor Python
interpreter is confused.
So, minimally, to fix it, you need to either pass arguments to the
function call or to remove the arguments from the function definition.
I'm not sure what your overall intent is, so it is hard to say.
I also wonder if you understand the role of the arguments in function
definitions. Several functions you defined take site as one of their
arguments, but do nothing with it other than rebind the name to the
result of a raw_input() call.
In that case, it isn't clear why you should have the argument. Compare
these:
IDLE 1.1.1
>>> def very_silly_print_function(the_argument):
the_argument = raw_input('What should I print?')
print the_argument
>>> def slightly_less_silly_print_function_no_arg():
the_value = raw_input('What should I print?')
print the_value
>>> def slightly_less_silly_print_function_arg(the_argument):
print the_argument
>>> very_silly_print_function('This will not be printed')
What should I print?This will be printed instead
This will be printed instead
>>> slightly_less_silly_print_function_no_arg()
What should I print?This will be printed
This will be printed
>>> slightly_less_silly_print_function_arg('As will this')
As will this
>>>
So, your functions that take site in as an argument and only reference
it by site = raw_input(some_prompt_here) are kind of like the
very_silly_print_function above. But, it is a bit worse than that. The
very_silly_print_function reassigns the name and then does something
with it. You only reassign. Then, when your function ends, you drop
the name on the floor :-)
Take a look at this:
>>> def name_dropper():
name_inside_function = raw_input('What is your moniker?')
>>> name_dropper()
What is your moniker?Brian
>>> name_inside_function
Traceback (most recent call last):
File "<pyshell#20>", line 1, in -toplevel-
name_inside_function
NameError: name 'name_inside_function' is not defined
>>>
The name name_inside_function only exists (so to speak) inside the
function. To make it meaningful in your top-level (i.e. not inside a
function of class) code, you've got to bind it in the top-level:
>>> name_inside_function = 'Misleadingly named string that exists at
top-level'
>>> name_inside_function
'Misleadingly named string that exists at top-level'
>>> name_dropper()
What is your moniker?Brian
>>> name_inside_function
'Misleadingly named string that exists at top-level'
>>>
But now there are two names name_inside_function. One in your function
scope, one in the top-level or global scope. To make the assignment to
the name inside the function affect your top-level name, you've got to
do something like:
>>> def name_keeper():
name_inside_function = raw_input('What is your moniker?')
return name_inside_function
>>> top_level_name = name_keeper()
What is your moniker?Brian
>>> top_level_name
'Brian'
>>>
(There are other ways, but that's enough for now.)
I hope that there is some help in all that :-) Best,
brian vdB
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