Enum TypeError 

pub enum TypeError {
    TypeMismatch {
        at_node: String,
        expected: String,
        got: String,
        context: Vec<String>,
    },
    EffectRowMismatch {
        at_node: String,
        expected: String,
        got: String,
        context: Vec<String>,
    },
    UnknownIdentifier {
        at_node: String,
        name: String,
    },
    ArityMismatch {
        at_node: String,
        expected: usize,
        got: usize,
    },
    NonExhaustiveMatch {
        at_node: String,
        missing: Vec<String>,
    },
    UnknownField {
        at_node: String,
        record_type: String,
        field: String,
    },
    DuplicateField {
        at_node: String,
        field: String,
    },
    UnknownVariant {
        at_node: String,
        constructor: String,
    },
    EffectNotDeclared {
        at_node: String,
        effect: String,
    },
    InfiniteType {
        at_node: String,
    },
    AmbiguousType {
        at_node: String,
    },
    RecursiveTypeWithoutConstructor {
        at_node: String,
        name: String,
    },
    RefinementViolation {
        at_node: String,
        fn_name: String,
        param_index: usize,
        binding: String,
        reason: String,
    },
    ExamplesOnEffectfulFn {
        at_node: String,
        fn_name: String,
    },
    ExampleArityMismatch {
        at_node: String,
        fn_name: String,
        case_index: usize,
        expected: usize,
        got: usize,
    },
    ExampleMismatch {
        at_node: String,
        fn_name: String,
        case_index: usize,
        expected: String,
        got: String,
    },
}

Variants

TypeMismatch

Fields

at_node: String

expected: String

got: String

context: Vec<String>

EffectRowMismatch

Two function types failed to unify specifically because their effect rows differ (#565). Effect rows unify by equality, not subtyping — a concrete row must match exactly, not merely be a superset or subset. This most often surfaces on record-field closures (e.g. Skill.handle, Tool.execute) whose declared row is fixed by the record type. Split out from TypeMismatch so the rule_tag names the invariance and the suggested fix steers toward narrowing the body rather than broadening the row.

Fields

at_node: String

expected: String

Pretty-printed expected effect row, e.g. [io, net].

got: String

Pretty-printed actual effect row found.

context: Vec<String>

UnknownIdentifier

Fields

at_node: String

name: String

ArityMismatch

Fields

at_node: String

expected: usize

got: usize

NonExhaustiveMatch

Fields

at_node: String

missing: Vec<String>

UnknownField

Fields

at_node: String

record_type: String

field: String

DuplicateField

Fields

at_node: String

field: String

UnknownVariant

Fields

at_node: String

constructor: String

EffectNotDeclared

Fields

at_node: String

effect: String

InfiniteType

Fields

at_node: String

AmbiguousType

Fields

at_node: String

RecursiveTypeWithoutConstructor

Fields

at_node: String

name: String

RefinementViolation

Refinement-type predicate provably violated at a call site (#209 slice 2). The type checker statically discharged the refinement and found the literal argument doesn’t satisfy the predicate. Slice 3 will add residual runtime checks for arguments that can’t be discharged statically.

Fields

at_node: String

fn_name: String

param_index: usize

binding: String

reason: String

ExamplesOnEffectfulFn

A function carrying signature-level examples (#369) declares at least one effect. v1 restricts examples to pure functions so the “same inputs ⇒ same outputs” invariant (rule #5) holds without modeling effect responses.

Fields

at_node: String

fn_name: String

ExampleArityMismatch

A signature-level example case (#369) supplies the wrong number of arguments for the function it documents.

Fields

at_node: String

fn_name: String

case_index: usize

Zero-based index of the failing case in the examples block.

expected: usize

got: usize

ExampleMismatch

A signature-level example case (#369 slice 2) ran successfully but the function’s actual output disagrees with the declared expected value. This is the load-bearing check that makes the examples block enforce behavior, not just types.

Fields

at_node: String

fn_name: String

case_index: usize

expected: String

Pretty-printed expected value (LHS of the => in the example).

got: String

Pretty-printed actual value the function body produced.

Implementations

impl TypeError

pub fn node(&self) -> &str

impl TypeError

pub fn rule_tag(&self) -> &'static str

Stable kebab-case identifier for this error variant. See all_rules for the full catalog.

pub fn rule_explanation(&self) -> &'static str

Plain-language description of what the rule enforces. Aimed at LLM repair-flow prompts: short enough to inline in a system message, specific enough to suggest the next move.

Trait Implementations

impl Clone for TypeError

fn clone(&self) -> TypeError

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for TypeError

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for TypeError

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Display for TypeError

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

Formats the value using the given formatter.

impl Error for TypeError

fn source(&self) -> Option<&(dyn Error + 'static)>

Returns the lower-level source of this error, if any.

fn description(&self) -> &str

👎Deprecated since 1.42.0:

use the Display impl or to_string()

fn cause(&self) -> Option<&dyn Error>

👎Deprecated since 1.33.0:

replaced by Error::source, which can support downcasting

fn provide<'a>(&'a self, request: &mut Request<'a>)

🔬This is a nightly-only experimental API. (error_generic_member_access)

Provides type-based access to context intended for error reports.

impl From<TypeError> for PositionedError

fn from(e: TypeError) -> Self

Converts to this type from the input type.

impl Serialize for TypeError

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

where __S: Serializer,

Serialize this value into the given Serde serializer.