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Type Guard — isArray

📖 Usage Example
function isArray(x: unknown): x is unknown[] {
  return Array.isArray(x)
}
isArray([1, 2])   // → true
isArray('abc')    // → false

Array.isArray() is the reliable way to check for arrays, handling cross-frame edge cases.

Type Guards: isArray

Challenge: Implement isArray(x: unknown): x is unknown[].

isArray([1, 2, 3])  // → true
isArray({})         // → false
💡 Hints (1)
  • • Array.isArray() is the standard way to check for arrays.