final class Generic<T> {
    func doSomething() {
        print("something") 
        
        // there is `po self` returns
        // expression produced error: error: Couldn't realize type of self. 
        // Try evaluating the expression with -d run-target
        // But `po print(self)` returns Generic<Swift.String>
        // and frame variable shows
        // (Generic<String>) self = 0x00006000007a0890 {}
    }
}

final class Normal {
    let example = Generic<String>()
    func doSomething() {
        example.doSomething() 

        // there is `po self` returns <Normal 0xAddr>
    }
}