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iOS Error Handling in Swift 2.0 Error Handling Cleaning Up With Defer

Mert Kahraman
Mert Kahraman
12,118 Points
Posted by Mert Kahraman
Mert Kahraman
12,118 Points

Multiple Defer Statements

Hi,

I'm confused while using multiple defer statements:

What if the following happens:

function with throws {

if someCondition { defer {someCode1} throw someError1 }

else { defer {someCode2} throw someError2 }

}

In this code, if the function early exits with the throw someError1 line, does only defer {someCode1} is executed? Or both defer statements are executed (with someCode2 first and someCode1 second)?

1 Answer

Krzysztof Growinski
Krzysztof Growinski
8,405 Points
Krzysztof Growinski
Krzysztof Growinski
8,405 Points

Hi, If the function hits the error your defer statements should be executed (both of them) unless you have a return statement of throw statement in the defer statement.

Check the documentation here https://developer.apple.com/library/ios/documentation/Swift/Conceptual/Swift_Programming_Language/ErrorHandling.html