Assorted optional chaining / binding examples

OptTest.swift

class A {
	var tInt: Int?
	var tDouble: Double?
	var tString: String?
	var tObj: B?

	func chainTest() {
		self.tObj?.tInt = 42
		self.tObj?.tDouble = 3.1415
		self.tObj?.tString = "Hello"
	}

	func letTest() {
		if let concreteThing = self.tObj {
			concreteThing.tInt = 42
			concreteThing.tDouble = 3.1415
			concreteThing.tString = "Hello"
		}
	}
}

class B {
	var tInt: Int?
	var tDouble: Double?
	var tString: String?
}

func chainTest(testObj: A?) {
	testObj?.tInt = 42
	testObj?.tDouble = 3.1415
	testObj?.tString = "Hello"
}

func letTest(testObj: A?) {
	if let concreteThing = testObj {
		concreteThing.tInt = 42
		concreteThing.tDouble = 3.1415
		concreteThing.tString = "Hello"
	}
}

var testObjA : A? = A()

chainTest(testObjA)
letTest(testObjA)
testObjA?.chainTest()
testObjA?.letTest()