PrimaryExpr TypeAssertion |
	PrimaryExpr Arguments .

Selector       = "." identifier .
Index          = "[" Expression [ "," ] "]" .
Slice          = "[" [ Expression ] ":" [ Expression ] "]" |
                 "[" [ Expression ] ":" Expression ":" Expression "]" .
TypeAssertion  = "." "(" Type ")" .
Arguments      = "(" [ ( ExpressionList | Type [ "," ExpressionList ] ) [ "..." ] [ "," ] ] ")" .
</pre>

- When configuring a JWT authenticator:
  
  If `username.expression` used 'claims.email', then 'claims.email_verified' must have been used in `username.expression` or `extra[*].valueExpression` or `claimValidationRules[*].expression`. An example claim validation rule expression that matches the validation automatically applied when `username.claim` is set to 'email' is 'claims.?email_verified.orValue(true)'.

- The "value" part in the `wait --for=jsonpath='{expression}'[=value]` is now
  optional. If the value is not provided i.e., the command looks like `wait --for=jsonpath='{expression}'`
  then the wait condition is interpreted as matched when the expression returns

- Added authorization check support to the CEL expressions of ValidatingAdmissionPolicy via a `authorizer`

### Promoted CRD Validation Expression Language to Beta

- Improved handling of jsonpath expressions for `kubectl wait --for`. It is now possible to use simple filter expressions which match on a field's content. ([#118748](https://github.com/kubernetes/kubernetes/pull/118748), [@andreaskaris](https://github.com/andreaskaris))

- Validation rules for Custom Resource Definitions can be written in the [CEL expression language](https://github.com/google/cel-spec) using the `x-kubernetes-validations` extension in OpenAPIv3 schemas (alpha). This is gated by the alpha "CustomResourceValidationExpressions" feature gate. ([#106051](https://github.com/kubernetes/k...

- Added ports autocompletion for kubectl port-foward command. ([#124683](https://github.com/kubernetes/kubernetes/pull/124683), [@TessaIO](https://github.com/TessaIO)) [SIG CLI]
- Added support for CEL(Common Expression Language) expressions and `additionalProperties` to be used under nested quantifiers in CRD schemas. ([#124381](https://github.com/kubernetes/kubernetes/pull/124381), [@alexzielenski](https://github.com/alexzielenski)) [SIG API Machinery]

- Added name validation for dynamic client methods in client-go ([#75072](https://github.com/kubernetes/kubernetes/pull/75072), [@lblackstone](https://github.com/lblackstone))
- CustomResourceDefinition with invalid regular expression in the pattern field of OpenAPI v3 validation schemas are no longer considered structural. ([#78453](https://github.com/kubernetes/kubernetes/pull/78453), [@sttts](https://github.com/sttts))

- Added a new feature gate `CelValidatingAdmissionExtensibility` to enable expression validation for Admission Control. ([#112792](https://github.com/kubernetes/kubernetes/pull/112792), [@cici37](https://github.com/cici37)) [SIG API Machinery]