Swift 2.0 guard giving me errors

Question

I was using the guard function and when I'd typed the guard statement below:

var IOUArray = [IOU(amount: 20, payer: "Isabella", description: 
"test"),IOU(amount: 30, payer: "Dad", description: "Test2")]
NSKeyedArchiver.archiveRootObject(IOUArray, toFile: "IOUArray")
guard
    let books = NSKeyedUnarchiver.unarchiveObjectWithFile("IOUArray") as? [IOU]

I got the error 'Expected else after guard condition' which wasn't a big deal because I wanted to put an else clause in anyway so I wrote:

else {return}

This time it threw up the error 'Return invalid outside of func' which was confusing and I have not seen this error before. So I then added nil to the state meant after return. Same Error. I don't know what is going on. Help will give you my infinite gratitude.

Rashwan L · Accepted Answer · 2016-01-03T01:40:53.947

2

Else error. The guard condition must have an else-keyword. We can think of a guard as an if-else with an empty "if" and a requirement that the control flow terminates in the "else."

Here is the correct code

var IOUArray = [IOU(amount: 20, payer: "Isabella", description:
    "test"),IOU(amount: 30, payer: "Dad", description: "Test2")]
NSKeyedArchiver.archiveRootObject(IOUArray, toFile: "IOUArray")
guard let books = NSKeyedUnarchiver.unarchiveObjectWithFile("IOUArray") as? [IOU] else {
   return
}

edited Jan 03 '16 at 01:40

answered Jan 03 '16 at 01:28

Rashwan L

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Then I get the error 'guard body may not fall through, consider using 'return' or 'break' to exit the scope. – needshelp Jan 03 '16 at 01:39
I just noticed that, and have updated the code by added a return in the else @needshelp – Rashwan L Jan 03 '16 at 01:41
Then I get the 'Return invalid outside of fun' error @Rashwan L – needshelp Jan 03 '16 at 02:59
@needshelp see my answer – user3441734 Jan 03 '16 at 05:45
Regarding "Return invalid outside of func" error: Is your guard expression written and executed in the scope of the playground? No function call, no return! – Jason Harrison Mar 15 '18 at 19:03

score 1 · Answer 2 · answered Jan 03 '16 at 05:42

1

error: return invalid outside of a func is reported by the compiler in the case you use returnstatement in global space. the else part of guard should never fall through, so if you remove return from it, another error occurs. check your code inside some function, to see the difference

answered Jan 03 '16 at 05:42

user3441734

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3

Right, so if you need to use guard in a non-returnable space then you should use `exit(1)` (from foundation) – Ezekiel Jan 03 '16 at 21:26
@EzekielElin Thanks for your note! import Darwin should be enough ( exit is declared in stdlib.h and as such is available on non apple platform as well ). – user3441734 Jan 04 '16 at 04:08
@user3441734 Global space? What do you mean? – needshelp Jan 04 '16 at 05:17

Swift 2.0 guard giving me errors

2 Answers2