output text/xml skipNullOn="everywhere"
---
a: {
  "a" @(attr1: null, attr2: "val", attr3: null): { "a": null, "b": true, "c": { "d" @(attr1: null, attr2: "val", attr3: null): false, "e": null} },
  "d": null,
  "e": "text",
  "f" @(a: "tato"): null
}