Issue #326
Traditionally, from Swift 4.2 we need guard let self
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| addButton.didTouch = { [weak self] in
guard
let self = self,
let product = self.purchasedProduct()
else {
return
self.delegate?.productViewController(self, didAdd: product)
}
|
This is cumbersome, we can invent a higher order function to zip and unwrap the optionals
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| func with<A, B>(_ op1: A?, _ op2: B?, _ closure: (A, B) -> Void) {
if let value1 = op1, let value2 = op2 {
closure(value1, value2)
}
}
addButton.didTouch = { [weak self] in
with(self, self?.purchasedProduct()) {
$0.delegate?.productViewController($0, didAdd: $1)
}
}
|