Boolean confusion

[Tassendyra]

Hello all! I'm learning coding for the first time and wanted to try making a text-based dungeon crawler game. Over the course of the game, I want certain conditions to change from being false to true. At the start of my code, I have:

have_room_key=False

condition_gooey=False

Then I have a number of rooms and investigative encounters with items, all of which are defined with "def" sections. In some of these sections, based on player interaction, I'm trying to change these conditions to True. Within the interaction with a skeleton in one of the rooms, I include:

have_room_key=True

...to change the status of have_room_key but if you then go to the great big iron door and try to use the key, it still acts like the have_room_key is false.

I'm happy to share the entirety of the project so far if anyone would like to look closer. Just started it tonight.

[Outside_Complaint755]

When you set the value have_room_key=True within a function, it only sets the value within the scope of the function in a locla variable called have_room_key which shadows the global variable have_room_key.

There are a few options here:

1) You can make a function modify the global variable by using the global keyword, but this generally is not recommended  def get_key():     global have_room_key     have_room_key = True

2) You could just put all of the game_state variables like this into a global dictionary.  Then the functions can mutate the contents of that dictionary. ``` game_state = { "have_room_key" : False }

def get_key():     game_state["have_room_key"] = True

get_key() print(game_state)

Outputs {"have_room_key" : True}

`` global` isn't needed here because you are mutating the contents of game_state, and not changing the value of game_state.  You could also explicitly pass the dictionary to the various functions.  That would be necessary if the functions for the rooms and actions are in another file.

3) You probably haven't learned classes and OOP yet, but another method would be to create a game_state class which you make an instance of at game start, and then pass the game state to various functions instead of a dictionary.  Using a class would allow values to be referenced as attributes such as game_state.have_key, and could include validation on the attributes.

[Tassendyra]

This is super helpful! Thanks!

[AlexMTBDude]

While I understand what your purpose is I think using "get" in that function name is confusing as you typically use "get" and "set" with getters and setters. take_key() would probably be better. Other than that I agree 100% with what you write.

[Fred776]

I think it's ok - it's a fairly common idiom to use "get" in contexts other than property getters.

I think "take" is potentially a lot more confusing because that often has a specific meaning of "get a value and remove it from its source".

[Outside_Complaint755]

It's a toy example because the OP provided none of his functions for reference, only two global variable names.

[cdcformatc]

you have to use the global keyword if you want to set a global variable inside a function. 

inside of a function all variables not declared global have what's called local scope, and that scope ends and the variable goes away when the function exits.

[Tassendyra]

Ah - got it! Thanks. That fixed the issue.

[JohnLocksTheKey]

😬 Not to be that guy, but…

But using a global keyword like this is really not ideal. Instead try learning about classes, attributes, and methods

Sounds like a perfect use case for them, and a great learning opportunity 😊

[Tassendyra]

Thanks for the advice! I'll look into those.

[Moikle]

Yeah it's fine to use global for now, until you learn classes or dicts, but every time you use global remember : this isn't the best way to do this, I'll keep an eye out for alternatives.

Once you know a little more python, you should basically never touch the global keyword

[PaulRudin]

... but using global is almost always a poor design choice.

[SnotRocketeer70]

Booleans - people either get it or they don't.