[Solved] Given this code snippet, what will happen if the network call fails? func fetchData() { URLSession.shared.dataTask(with:... Given this code snippet, what will happen if the network call fails? | iOS Swift

iOS Swift - Networking

Given this code snippet, what will happen if the network call fails?

func fetchData() {
  URLSession.shared.dataTask(with: url) { data, response, error in
    guard error == nil else {
      print("Failed with error")
      return
    }
    print("Data received")
  }.resume()
}

ACrashes because error is not unwrapped

BPrints "Data received" even if error exists

CDoes nothing because resume() is missing

DPrints "Failed with error" and returns early

Step-by-Step Solution

Solution:

Step 1: Understand guard statement usage
The guard checks if error is nil; if not, it prints failure and returns early.
Step 2: Confirm resume() call
resume() is called, so the task runs and closure executes.
Final Answer:
Prints "Failed with error" and returns early -> Option D
Quick Check:
Guard error check returns on error = Prints "Failed with error" and returns early [OK]

Quick Trick: guard error == nil else returns early on failure [OK]

Common Mistakes:

Assuming data received prints despite error
Thinking error must be unwrapped forcibly
Forgetting resume() disables task

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More iOS Swift Quizzes

Given this code snippet, what will happen if the network call fails?

Step 1: Understand guard statement usage

Step 2: Confirm resume() call

Final Answer:

Quick Check:

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