Swift Language Blocks Non-escaping closure
Example
In Swift 1 and 2, closure parameters were escaping by default. If you knew your closure wouldn’t escape the function body, you could mark the parameter with the @noescape attribute.
In Swift 3, it’s the other way around: closure parameters are non-escaping by default. If you intend for it to escape the function, you have to mark it with the @escaping attribute.
class ClassOne {
// @noescape is applied here as default
func methodOne(completion: () -> Void) {
//
}
}
class ClassTwo {
let obj = ClassOne()
var greeting = "Hello, World!"
func methodTwo() {
obj.methodOne() {
// self.greeting is required
print(greeting)
}
}
}
