I’m making a little utility struct that needs to be able to wrap an arbitrary
value, which may be an optional, and be able to tell whether it’s nil. So I
declared it like this (I’ve removed the interesting/useful parts of the code
leaving just the constructors and one property):
public struct check<T> {
let actual: T?
public init(_ a: T) {
actual = a
}
public init(_ a: T?) {
actual = a
}
public var isNil: Bool {
return actual == nil
}
}
This works fine, except when I try to use it with a value of type `Any?`:
let str: String = "Hi"
check(str).isNil // false
let maybe: String? = nil
check(maybe).isNil // true
let hmm: Any? = nil
check(hmm).isNil // Error: “Ambiguous use of ‘init'"
(I agree that `Any?` is sort of a weird type; in my code it represents a value
that might be a JSON object. NSJSONSerialization parses to type `Any`, but
there might not be a value, so it becomes an Optional<Any> or Any?.)
This worked in Swift 2.2, but after upgrading to Swift 3 [in the latest Xcode 8
beta] the compiler started complaining.
How can I fix the `check` struct's constructor(s) to make this work?
—Jens_______________________________________________
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