FunctionCaptureValue.swift

class Person {
    let name: String
    
    init(name: String) {
        self.name = name
    }
    
    func introduce() {
        print("Hi I am \(name)!")
    }
    
    func greet(personName: String) {
        print("Hey \(personName). My name is \(name) 😊")
    }
}

var person: Person? = Person(name: "Neel")
var greetPerson = person?.greet // printName is of type (String) -> Void which seems like it's referenced as a closure

var performGreeting = { [greetPerson] in
    greetPerson?("Ron")
}
greetPerson = nil
person = nil // Even though person here becomes nil, the greetPerson function is captured in the performGreeting closure
performGreeting() // Since greetPerson is captured, it will also capture the person value within the function and this will print out Hey Ron. My name is Neel 😊