Agenda Warmup Lesson 2.2 (parameters, etc) ppt download(07) Save Image Image gallery: Cannot Use Mutating Member On Immutable Value 'self' Is Immutable
![[WWDC19] Data Flow Through SwiftUI](https://velog.velcdn.com/images/marisol/post/96b6fb47-60fd-453c-b6d0-01c7258ecbf7/image.png "[WWDC19] Data Flow Through SwiftUI")
![[WWDC19] Data Flow Through SwiftUI](https://velog.velcdn.com/images/marisol/post/0a46b53f-ccf0-49d8-84a6-4f2801eb5236/image.png "[WWDC19] Data Flow Through SwiftUI")
![Array Immutable value of type '[String]' only has mutating member](https://i.ytimg.com/vi/epbXme7GjfM/maxresdefault.jpg "Array Immutable value of type '[String]' only has mutating member")
