Enum Operator 

#[non_exhaustive]
pub enum Operator {
    And,
    Or,
    Not,
}

Logical operator for combining filter conditions (RFC 8620 §5.5).

Excluded from extras preservation

This enum is out of scope for the workspace extras-preservation policy: it carries no Other(String) catch-all variant, and backends must dispatch on its known variants (AND, OR, NOT) to evaluate a filter tree. An Other operator would be meaningless — a server that cannot interpret the operator cannot evaluate the filter, and silently round- tripping it back to the client would yield wrong query results.

More broadly, filter algebra (this enum and the per-object FilterCondition / Comparator types) is excluded because unrecognised filter clauses are a query-correctness hazard: silently dropping or round-tripping a clause the server does not understand can return the wrong set of records to the client without any error signal.

What to do instead

IETF-track path. Vendors who need both capability-level declaration and filterability for custom fields should use draft-ietf-jmap-metadata (capability URI urn:ietf:params:jmap:metadata), which adds namespace-keyed metadata / privateMetadata properties to each listed data type, with per-type schema discovery via the capability’s dataTypes (namespaces / supportsVendorNamespaces / maxDepth) and metadataExists / metadataTextContains / metadataTextEquals conditions on that type’s own /query filter (draft-ietf-jmap-metadata-04 §1.2.1, §3.6). Helpers live in jmap-metadata-types, jmap-metadata-server, and jmap-metadata-client.

Pre-IETF escape. Vendors who cannot wait for the metadata draft can either escape the filter tree to serde_json::Value or fork the per-crate FilterCondition type. See crate-jmap-calendars-types/PLAN.md for the hybrid sloppy-value pattern.

Cross-reference: bd JMAP-lbdy “Decision: filter algebra excluded”.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

And

Logical AND: all sub-filters must match (RFC 8620 §5.5).

Or

Logical OR: at least one sub-filter must match (RFC 8620 §5.5).

Not

Logical NOT: none of the sub-filters may match (RFC 8620 §5.5).

Trait Implementations

impl Clone for Operator

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Operator

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for Operator

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Eq for Operator

impl PartialEq for Operator

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl Serialize for Operator

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for Operator