View has - by default - a Body of type Never.

[filip-sakel]

This introduces bugs and almost defeats the purpose of compile-time errors. To prevent the program compiling successfully without producing an error for a type like Foo:

struct Foo: View {
    
}

There are two options - that I can think of:

1. Add another _Never conditional conformances - to a dummy type like _Never that will require disambiguating when omitting the body:

   enum _Never: View {
       var body: Never { fatalError() }
   }
   
   extension View where Body == _Never {
       var body: _Never {
           fatalError("Can't access body of Never View.")
       }
   }

   That is a hack though and the error ("Type 'H' does not conform to protocol 'Block'") doesn't provide a fix possibly leaving a novice developer confused.

2. Remove the extension that provides an automatic conformance when Body is of type Never and move that behaviour to the ViewDeferredToRenderer protocol - or to an underlying view protocol such as _StuctureView, _View, _FatalView:

   protocol _StuctureView: View where Body == Never {}
   
   extension _StuctureView {
        var body: Never {
           fatalError("Can't access body of Structure View.")
       }
   }

   That IMO is the best option, as it avoids automatic type-inference altogether and provides a useful error message - that offers a fix.

[MaxDesiatov]

Thank you @filip-sakel, this is a great point, primarily because it also highlights the incompatibility with SwiftUI, it is now fixed in the main branch.