Help: Updating one dictionary value changes value for same key in all other dictionaries

[Jokster]

Godot Version

v4.2.stable

Question

I am losing my mind over a dictionary saving issue, which I rebuilt here very simplified:

---

Code example:

#initiate two different empty dictionaries
var save_data: Dictionary = {}
var game_data: Dictionary = {}

func _ready():
#inst. some game data
game_data = {“SomeText”: “Stone”}

#save current game data
save_data = game_data

#change a variable in game data to simulate game running
game_data[“SomeText”] = “Lava”

#print compare values
print(game_data[“SomeText”])
print(save_data[“SomeText”])

---

Returns:
“Lava”
“Lava”

---

I absolutely do not understand why the “SomeText” filed in “save_game” also gets changed and would have expected to receive “Lava” “Stone” as outcomes.

I am trying to use this to temporally save a bunch of current game data in “save_game” have to game continuing in “game_data” and be able to jump back to the old data in “save_game”. However, in this example both dictionaries are always 100% the same and do not have any added value

Any hint to what I am missing is highly appreciated!

Best and 1000 thanks
Jokster

[FencerDevLog]

@Jokster

save_data = game_data

This line doesn’t actually save anything, only makes both variables point to the same dictionary object. Try to use duplicate() instead.

Dictionary

[Jokster]

You are my absolute hero. The following fixes the logic and works as a charm:

save_data = game_data.duplicate(true)