class A { unowned lazy var hoge: B = B() } class B {}Playground execution failed: error: cannot convert return expression of type 'B' to return type 'B' error: MyPlayground.playground:4:32: error: cannot convert value of type 'B' to specified type 'B' unowned lazy var hoge: B = B() ^~~ error: cannot assign value of type 'B' to type 'B?' error: cannot assign value of type 'B' to type 'B?'hoge: B! だとなんか違う怒られする