[Solved] What is wrong with this Swift code snippet? await withTaskGroup(of: Int.self) { group in group.addTask { 5 } group.addTask { 10 } var total = 0 for value in group { total += value } print(total) } | iOS Swift

iOS Swift - Concurrency

What is wrong with this Swift code snippet?

await withTaskGroup(of: Int.self) { group in
  group.addTask { 5 }
  group.addTask { 10 }
  var total = 0
  for value in group {
    total += value
  }
  print(total)
}

ACannot add tasks returning Int

BMissing await keyword before for loop iteration

CTaskGroup must be declared with var keyword

Dprint statement must be inside a Task

Step-by-Step Solution

Solution:

Step 1: Review for-await syntax
When iterating over a TaskGroup, the for loop must be 'for await' to await each task's result.
Step 2: Identify missing await
The code uses 'for value in group' instead of 'for await value in group'.
Final Answer:
Missing await keyword before for loop iteration -> Option B
Quick Check:
Use 'for await' to iterate TaskGroup results [OK]

Quick Trick: Always use 'for await' to iterate TaskGroup results [OK]

Common Mistakes:

Using regular for loop without await
Thinking addTask can't return values
Misplacing print statement

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What is wrong with this Swift code snippet?

Step 1: Review for-await syntax

Step 2: Identify missing await

Final Answer:

Quick Check:

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