[Solved] Find the bug in this code:let defaults = UserDefaults.standard defaults.set(3.14, forKey: "pi") let piValue = defaults.double(forKey: "pi") print(piValue) | iOS Swift

iOS Swift - Local Data Persistence

Find the bug in this code:

let defaults = UserDefaults.standard
defaults.set(3.14, forKey: "pi")
let piValue = defaults.double(forKey: "pi")
print(piValue)

AKey "pi" must be declared before use

BNo bug; code works correctly

CMust cast value to Double when setting

Ddouble(forKey:) returns Int, not Double

Step-by-Step Solution

Solution:

Step 1: Review saving and retrieving Double
The code saves 3.14 as Double and retrieves it with double(forKey:).
Step 2: Confirm no errors
Both methods are correct and no casting or declaration is needed.
Final Answer:
No bug; code works correctly -> Option B
Quick Check:
Saving and reading Double works as shown [OK]

Quick Trick: double(forKey:) returns 0.0 if key missing, else saved Double [OK]

Common Mistakes:

Master "Local Data Persistence" in iOS Swift

9 interactive learning modes - each teaches the same concept differently

More iOS Swift Quizzes

Find the bug in this code: