pub fn observable_object() -> &'static ConformanceExpand description
An ObservableObject conformance on Foundation.JSONDecoder.
Three requirements, and the protocol has defaults for two of them: the
associated ObjectWillChangePublisher and its Publisher conformance both
come from the constrained extension where that type is
ObservableObjectPublisher. Only the getter has to be supplied, and it
forwards to Combine’s own default — so what this builds is the same table
extension JSONDecoder: ObservableObject {} compiles to, which is what lets
the parity reference declare exactly that and dump the same value.
The object this hangs on used to be ImageRenderer<AnyView>, the one class
in SwiftUI that already conforms. That worked, but nothing could check it:
reflecting into a live ImageRenderer faults, so the three modifiers taking
an ObservableObject had no parity case at all. A JSONDecoder dumps in
two lines.