Struct McpError 

pub struct McpError {
    pub code: i64,
    pub message: String,
    pub data: Expr,
}

The error object inside an McpErrorEnvelope.

Fields

code: i64

The numeric error code (see the constants in this crate, e.g. INTERNAL_ERROR).

message: String

A human-readable error message.

data: Expr

Optional structured error data.

Trait Implementations

impl Citizen for McpError

fn citizen_symbol() -> Symbol

The citizen’s namespace/name class symbol.

fn citizen_version() -> u32

The citizen’s encoding version.

fn citizen_arity() -> usize

Number of constructor fields (excluding the version argument).

fn citizen_fields() -> &'static [&'static str]

The citizen’s field names, in constructor order.

impl CitizenField for McpError

fn encode_field(&self) -> Expr

Encodes the field value as its constructor Expr.

fn decode_field_expr(expr: &Expr, field: &'static str) -> Result<Self>

Decodes the field from a constructor Expr, naming field in errors.

fn decode_field_value( cx: &mut Cx, value: Value, field: &'static str, ) -> Result<Self, Error>

Decodes the field from a runtime Value via its Expr projection.

impl CitizenRuntime for McpError

fn construct_from_values(cx: &mut Cx, args: Vec<Value>) -> Result<Self>

Builds the citizen from decoded constructor argument values.

fn example() -> Self

Returns the canonical example value used as a conformance fixture.

impl Clone for McpError

fn clone(&self) -> McpError

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for McpError

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

Formats the value using the given formatter.

impl Default for McpError

fn default() -> Self

Returns the “default value” for a type.

impl Object for McpError

fn display(&self, cx: &mut Cx) -> Result<String>

Render the object as a human-readable display string.

fn as_any(&self) -> &dyn Any

Expose the object for Rust downcasting.

fn header(&self) -> &ObjectHeader

Identity and trust header for the object; defaults to the shared anonymous header.

fn op(&self, _key: &OpKey) -> Option<&dyn Op>

Resolve the operation registered under key, if any.

fn claims( &self, _cx: &mut Cx, _pattern: &ClaimPattern, _sink: &mut dyn ClaimSink, ) -> Result<(), Error>

Emit the object’s claims matching pattern into sink.

fn snapshot(&self, _cx: &mut Cx) -> Result<Option<Datum>, Error>

Optional content-addressable snapshot of the object’s state.

impl ObjectCompat for McpError

fn class(&self, cx: &mut Cx) -> Result<ClassRef>

Class object this value belongs to; defaults to nil.

fn as_expr(&self, cx: &mut Cx) -> Result<Expr>

Expression form of the object; defaults to an opaque extension node.

fn as_object_encoder(&self) -> Option<&dyn ObjectEncode>

Object-encoder view, if the object encodes other objects.

fn as_callable(&self) -> Option<&dyn Callable>

Callable view, if the object can be invoked.

fn as_class(&self) -> Option<&dyn Class>

Class view, if the object is a class.

fn as_shape(&self) -> Option<&dyn Shape>

Shape view, if the object is a shape.

fn as_read_constructor(&self) -> Option<&dyn ReadConstructor>

Read-constructor view, if the object decodes data forms.

fn as_number_domain(&self) -> Option<&(dyn NumberDomain + 'static)>

Number-domain view, if the object is a number domain.

fn as_number_value(&self) -> Option<&dyn NumberValue>

Number-value view, if the object is a domain number.

fn as_eval_fabric(&self) -> Option<&dyn EvalFabric>

Eval-fabric view, if the object is a distributed eval surface.

fn as_stream(&self) -> Option<&dyn Stream>

Stream view, if the object is a stream.

fn as_sequence(&self) -> Option<&dyn Sequence>

Sequence view, if the object is a sequence.

fn as_thunk(&self) -> Option<&dyn Thunk>

Thunk view, if the object is a deferred computation.

fn as_list(&self) -> Option<&(dyn ListValue + 'static)>

List view, if the object is a list value.

fn as_table_impl(&self) -> Option<&(dyn Table + 'static)>

Table-implementation view, if the object is a table.

fn as_dir(&self) -> Option<&(dyn Dir + 'static)>

Directory view, if the object is a directory.

fn truth(&self, _cx: &mut Cx) -> Result<bool, Error>

Truthiness of the object; defaults to true.

fn publish_shape_satisfaction_claims( &self, _cx: &mut Cx, _shape: &Ref, ) -> Result<bool, Error>

Publish claims asserting that the object satisfies shape; returns whether any were published.

fn as_table(&self, cx: &mut Cx) -> Result<Value, Error>

Project the object into a table value; the default exposes its display.

impl ObjectEncode for McpError

fn object_encoding(&self, _cx: &mut Cx) -> Result<ObjectEncoding>

Returns the ObjectEncoding this object should be rendered as.

impl PartialEq for McpError

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl StructuralPartialEq for McpError