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iOS Intermediate Swift 2 Extensions and Protocols Extensions and Protocols

Wai Hong Low
PLUS
Wai Hong Low
Courses Plus Student 6,859 Points

intermediate swift 2 quiz

protocol SomeProtocol { func someMethod() -> Int }

extension SomeProtocol { func someMethod() -> Int { return 1 } }

struct SomeStruct: SomeProtocol { func someMethod() -> Int { return 2 } }

let b: SomeProtocol = SomeStruct() b.someMethod()

What is the value returned from the someMethod() call

I thought it's suppose to be 1 instead 2?

1 Answer

No, 2 is correct because SomeStruct adheres to the SomeProtocol and overrides the SomeMethod method - so when you call SomeMethod on your object b it's calling the method that returns 2.