[Solved] Find the error in this Swift code:let numbers = [1, 2, 3] let doubled = numbers.map { num in num * 2 } | iOS Swift

iOS Swift - Swift Language Essentials

Find the error in this Swift code:

let numbers = [1, 2, 3]
let doubled = numbers.map { num in
  num * 2
}

Amap cannot be used with closures

BNo error, code is correct

CClosure parameter missing type

DMissing return keyword inside closure

Step-by-Step Solution

Solution:

Step 1: Review map and closure usage
map accepts a closure; 'num in num * 2' is valid shorthand syntax.
Step 2: Confirm no syntax errors
Return keyword is optional for single-expression closures.
Final Answer:
No error, code is correct -> Option B
Quick Check:
map with closure syntax = correct [OK]

Quick Trick: Single-expression closures omit 'return' [OK]

Common Mistakes:

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