swift - Editor placeholder in source file -


following arkit tutorial https://www.youtube.com/watch?v=r8u8rgdmop4

but getting

editor placeholder in source file

error in following code (2nd line). has there been change in swift cause this?

override func viewwillappear(_ animated: bool) {     super.viewwillappear(animated)     let configuration = arworldtrackingsessionconfiguration()     sceneview.session.run(configuration)     addobject() }

there placeholder in file, meaning you'll see grey or blue block, that'll value, indicating need replace placeholder of value.

the gray blocks in image placeholders.

it possible xcode being idiotic, try cleaning project, run again.


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