Swift - Functions
Identify the error in this Swift function declaration:
func add(numbers: Int...) -> Int {
return numbers.reduce(0, +)
}
add(1, 2, 3)Identify the error in this Swift function declaration:
medium📝 Debug Q6 of 15
Step-by-Step Solution
Solution:
Step 1: Check function call syntax
The function parameter has an external name 'numbers', so call must use it or use underscore in declaration.Step 2: Identify call error
Calling add(1, 2, 3) without 'numbers:' causes error; correct call is add(numbers: 1, 2, 3) or declare with underscore.Final Answer:
Missing underscore before parameter name in call -> Option AQuick Check:
Parameter name required unless underscore used [OK]
Quick Trick: Use _ to omit external parameter name or include it in call [OK]
Common Mistakes:
- Assuming variadic cannot use reduce
- Ignoring external parameter names
- Thinking variadic must be last always (true but not error here)
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