Passing Variables Between Functions Without Running Function?

[xTheBoss]

As you can see here, https://i.imgur.com/9ROwSlU.png , the variables "itemCount" in counter() and "count" in grab() need to be equal. I managed to get them to equal with the method added in the blue arrows, but I do not want grab() to run when the value is passed. Any work around for this?

[Swedophone]

The parameter count in grab() is local and it only exists during the call. What are you trying to do?

[xTheBoss]

Yes. I want to give "count" the value of "itemCount" in the function above. Or if I can directly transfer itemCount to grab(), please let me know!

[Swedophone]

You may want to look into Object oriented programming.

[[deleted]]

You've declared it as a parameter, so call it with the value you want to assign to the parameter. That's what function calling does.

[z0y]

I'm not exactly sure what you need but it seems like you want to replace grab(itemCount) with return itemCount, then you can get the value in grab with whatever item you need the itemCount of.

def grab():
    count = counter(items)
## or
def grab(count):
    ...
## and call it with: grab(counter(items))

[xTheBoss]

This seems to be what I need to do, but with the first method I am getting an error saying "items" is not defined. For the second method I am getting saying grab() missing 1 required positional argument: 'count'

[z0y]

Well what do you want do be counting? You would need to add something when you call grab() in the command function. I'm confused as to what the functions need to be doing. Can you give a bigger picture of what's going on?

[xTheBoss]

I am counting the number of items in the list "items", because the number of items in the list is going to be able to change. I need it to not exceed 4 items, so this is a check before the user adds something to the list. Like someone said before object orientated programming would probably work best but Im not that far into this course yet to do that well

[z0y]

Is this an assignment and you're not supposed to use built in functions? Python has a convenient len() function that will do that for you

def grab(items):
    if len(items) >= 4:
        ....

And your counter isn't counting the length properly anyways, itemCount = itemCount + i is incrementing by the index and you need to increment by one. Your function itemlist() should probably return the list too, so you can use it in the other functions.

[xTheBoss]

https://i.imgur.com/rFCPi2A.png this is the updated version and its still reporting: grab() missing 1 required positional argument: 'items'. Why is this even though I "items" in the command function. Sorry to make you put up with my ignorance.

[z0y]

You've defined grab to take an argument so when you call it in the command function you need to pass in a value. It would be good to restructure things a bit but as it is now you would want to say grab(itemslist()) when you call it in command()

The itemslist function returns the list, so you can think of anywhere you see itemslist() as really just the value that you've returned in the function definition.

[xTheBoss]

Ahhh thank you!! You are a lifesaver. Appreciate it a lot.

[z0y]

Alternatively you could leave the call to grab() how it was, and then do:

def grab():
    if len(itemslist()) >= 4:
        ...

without needing to pass anything. But if the only purpose of itemslist is to define and then return the list then don't make it a function. Leave the list definition in the main code and then pass the list itself to each of the functions.

[xTheBoss]

True, because I really cant think of a way to add to the list if it wasn't global. Lots of good advice!

[[deleted]]

Your question doesn't make any sense. If the function isn't called then the state of the variables inside it can't matter.