The $dynamicAnchor keyword allows the creation of plain name fragments that are not tied to a particular structural location within a schema. This is particularly useful for making subschemas reusable and relocatable without needing to update JSON Pointer references. Unlike $anchor, $dynamicAnchor indicates an extension point when used with the $dynamicRef keyword, facilitating the extension of recursive schemas without imposing specific semantics on that extension. Without $dynamicRef, $dynamicAnchor behaves the same as $anchor.

Examples

{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://example.com/root",
  "$ref": "list",
  "$defs": {
    "foo": {
      "$dynamicAnchor": "items",
      "type": "string"
    },
    "list": {
      "$id": "list",
      "type": "array",
      "items": {
        "$dynamicRef": "#items"
      },
      "$defs": {
        "items": {
          "$dynamicAnchor": "items",
          "type": "number"
        }
      }
    }
  }
}

[ "foo", "bar" ]

[ "foo", 42 ]

Note: A $dynamicRef referencing a $dynamicAnchor within the same schema resource functions similarly to a standard $ref referencing an $anchor. Similarly, a $dynamicRef referencing an $anchor within the same schema resource behaves like a typical $ref referencing an $anchor. Likewise, a $ref targeting a $dynamicAnchor within the same schema resource behaves like a regular $ref targeting an $anchor.