docs: note about JSON Pointer extensions

Author: jg-rp

docs/index.md

@@ -4,7 +4,7 @@ JSONPath is a mini language for selecting objects from data formatted in JavaScr
 
 Python JSONPath is a non-evaluating, read-only implementation of JSONPath, suitable for situations where JSONPath query authors are untrusted. We follow most of the [IETF JSONPath draft](https://datatracker.ietf.org/doc/html/draft-ietf-jsonpath-base-13). See [Notable differences](syntax.md#notable-differences) for a list of areas where we deviate from the standard.
 
-Since version 0.8.0, we also include implementations of [JSON Pointer](api.md#jsonpath.JSONPointer) ([RFC 6901](https://datatracker.ietf.org/doc/html/rfc6901)) and [JSON Patch](api.md#jsonpath.JSONPatch) ([RFC 6902](https://datatracker.ietf.org/doc/html/rfc6902)), plus methods for converting a [JSONPathMatch](api.md#jsonpath.JSONPathMatch) to a `JSONPointer`.
+Since version 0.8.0, we also include implementations of [JSON Pointer](pointers.md) ([RFC 6901](https://datatracker.ietf.org/doc/html/rfc6901)) and [JSON Patch](api.md#jsonpath.JSONPatch) ([RFC 6902](https://datatracker.ietf.org/doc/html/rfc6902)), plus methods for converting a [JSONPathMatch](api.md#jsonpath.JSONPathMatch) to a `JSONPointer`.
 
 ## Install
 

docs/pointers.md

@@ -6,6 +6,9 @@ JSON Pointer ([RFC 6901](https://datatracker.ietf.org/doc/html/rfc6901)) is a st
 
 JSON Pointers are a fundamental part of JSON Patch ([RFC 6902](https://datatracker.ietf.org/doc/html/rfc6902)). Each patch operation must have at least one pointer, identifying the target value.
 
+!!! note
+    We have extended RFC 6901 to handle our non-standard JSONPath [keys selector](syntax.md#keys-or) and index/property pointers from [Relative JSON Pointer](#torel).
+
 ## `resolve(data)`
 
 Resolve this pointer against _data_. _data_ can be a file-like object or string containing JSON formatted data, or a Python [`Mapping`](https://docs.python.org/3/library/collections.abc.html#collections.abc.Mapping) or [`Sequence`](https://docs.python.org/3/library/collections.abc.html#collections.abc.Sequence), like a dictionary or list.