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iOS Swift Functions and Optionals Optionals Optional Chaining

I get this error in the example with optionals/optionals chaining:


I guess the compiler is complaining about the String format in the array is not equal to the String format in the function parameter?

PS: Im a noob. Handle with care :)

2 Answers

The compiler is telling you that the array "aptNumbers" is not a String, it's an array, and can't be converted into a String. What's the problem here? You're comparing a String to an Array in your for-in loop. You should trying comparing "tempAptNumbers," which is a String object in the array "aptNumbers" to another String. Replace "aptNumbers" in your for-in loop to something like "404" and see what you get.

if (tempAptNumber == aptNumber) { return aptNumber }