it actually satisfies the interface.
If a type—for example,
<code><a href="/pkg/encoding/json/#RawMessage">json.RawMessage</a></code>—needs
-a custom its JSON representation, it should implement
+a custom JSON representation, it should implement
<code>json.Marshaler</code>, but there are no static conversions that would
cause the compiler to verify this automatically.
If the type inadvertently fails to satisfy the interface, the JSON encoder will still work,