Enum ErrorKind 

pub enum ErrorKind {
    UnexpectedCharacter(char),
    InvalidInteger,
    InvalidFloat,
    InvalidStringEscape(char),
    UnterminatedString,
    EmptyCharLit,
    UnterminatedCharLit,
    MultiCharLit,
    InvalidCharEscape,
    InvalidUnicodeEscape,
    UnexpectedToken {
        expected: Cow<'static, str>,
        found: Cow<'static, str>,
    },
    UnexpectedEof {
        expected: Cow<'static, str>,
    },
    ParseError(String),
    CFfi(String),
    NoMainFunction,
    UndefinedVariable(String),
    UndefinedFunction(String),
    AssignToImmutable(String),
    UnknownType(String),
    UseAfterMove(String),
    CannotMoveField {
        type_name: String,
        field: String,
    },
    TypeMismatch {
        expected: String,
        found: String,
    },
    WrongArgumentCount {
        expected: usize,
        found: usize,
    },
    MissingFields(Box<MissingFieldsError>),
    UnknownField {
        struct_name: String,
        field_name: String,
    },
    PrivateField {
        struct_name: String,
        field_name: String,
    },
    DuplicateField {
        struct_name: String,
        field_name: String,
    },
    MissingFieldInDestructure {
        struct_name: String,
        field: String,
    },
    EmptyStruct,
    EmptyAnonEnum,
    ReservedTypeName {
        type_name: String,
    },
    DuplicateTypeDefinition {
        type_name: String,
    },
    LinearValueNotConsumed(String),
    LinearStructCopy(String),
    LinearStructClone(String),
    CloneStructNonCopyField(Box<CloneStructNonCopyFieldError>),
    PostureMismatch(Box<PostureMismatchError>),
    UnknownDirective {
        name: String,
        note: Option<String>,
    },
    UnknownMarker {
        name: String,
        note: Option<String>,
    },
    MarkerNotApplicable {
        marker: String,
        item_kind: &'static str,
    },
    ConflictingThreadSafetyMarkers {
        type_name: String,
    },
    SpawnArgNotSend {
        arg_type: String,
    },
    SpawnReturnNotSend {
        fn_name: String,
        ret_type: String,
    },
    SpawnArgIsRef {
        arg_type: String,
    },
    SpawnArgIsLinear {
        arg_type: String,
    },
    SpawnFunctionWrongArity {
        fn_name: String,
        arity: usize,
    },
    SpawnFunctionNotFound {
        name: String,
    },
    DuplicateMethod {
        type_name: String,
        method_name: String,
    },
    DeriveDirectFieldAccess {
        derive_name: String,
        method_name: String,
    },
    DeriveNotADerive {
        name: String,
        found: String,
    },
    UndefinedMethod {
        type_name: String,
        method_name: String,
    },
    UndefinedAssocFn {
        type_name: String,
        function_name: String,
    },
    MethodCallOnNonStruct {
        found: String,
        method_name: String,
    },
    MethodCalledAsAssocFn {
        type_name: String,
        method_name: String,
    },
    AssocFnCalledAsMethod {
        type_name: String,
        function_name: String,
    },
    DuplicateDestructor {
        type_name: String,
    },
    DestructorUnknownType {
        type_name: String,
    },
    InvalidInlineDrop {
        type_name: String,
        reason: String,
    },
    DuplicateConstant {
        name: String,
        kind: String,
    },
    ConstExprNotSupported {
        expr_kind: String,
    },
    DuplicateVariant {
        enum_name: String,
        variant_name: String,
    },
    UnknownVariant {
        enum_name: String,
        variant_name: String,
    },
    UnknownEnumType(String),
    FieldWrongOrder(Box<FieldWrongOrderError>),
    FieldAccessOnNonStruct {
        found: String,
    },
    InvalidAssignmentTarget,
    InoutNonLvalue,
    InoutExclusiveAccess {
        variable: String,
    },
    BorrowNonLvalue,
    MutateBorrowedValue {
        variable: String,
    },
    MoveOutOfBorrow {
        variable: String,
    },
    BorrowInoutConflict {
        variable: String,
    },
    InoutKeywordMissing,
    BorrowKeywordMissing,
    ReferenceEscapesFunction {
        type_name: String,
    },
    BreakOutsideLoop,
    BreakInConsumingForLoop {
        element_type: String,
    },
    ContinueOutsideLoop,
    IntrinsicRequiresChecked(String),
    UncheckedCallRequiresChecked(String),
    UncheckedDestructor,
    ExternFnMissingUnchecked {
        fn_name: String,
        library: String,
    },
    InterfaceMethodUncheckedMismatch(Box<InterfaceMethodUncheckedMismatchError>),
    NonExhaustiveMatch {
        missing: Vec<String>,
    },
    EmptyMatch,
    InvalidMatchType(String),
    UnknownIntrinsic(String),
    IntrinsicWrongArgCount {
        name: String,
        expected: usize,
        found: usize,
    },
    IntrinsicTypeMismatch(Box<IntrinsicTypeMismatchError>),
    ImportRequiresStringLiteral,
    ModuleNotFound {
        path: String,
        candidates: Vec<String>,
    },
    StdLibNotFound,
    PrivateMemberAccess {
        item_kind: String,
        name: String,
    },
    UnknownModuleMember {
        module_name: String,
        member_name: String,
    },
    LiteralOutOfRange {
        value: u64,
        ty: String,
    },
    CannotNegateUnsigned(String),
    ChainedComparison,
    IndexOnNonArray {
        found: String,
    },
    ArrayLengthMismatch {
        expected: u64,
        found: u64,
    },
    IndexOutOfBounds {
        index: i64,
        length: u64,
    },
    TypeAnnotationRequired,
    MoveOutOfIndex {
        element_type: String,
    },
    LinkError(String),
    UnsupportedTarget(String),
    PreviewFeatureRequired {
        feature: PreviewFeature,
        what: String,
    },
    InterfaceMethodMissing(Box<InterfaceMethodMissingData>),
    InterfaceMethodSignatureMismatch(Box<InterfaceMethodSignatureMismatchData>),
    RefutablePatternInLet,
    ComptimeEvaluationFailed {
        reason: String,
    },
    ComptimeArgNotConst {
        param_name: String,
    },
    ComptimeUserError(String),
    InvalidLangItem {
        reason: String,
    },
    InternalError(String),
    InternalCodegenError(String),
}

The kind of compilation error.

Variants

UnexpectedCharacter(char)

InvalidInteger

InvalidFloat

InvalidStringEscape(char)

UnterminatedString

EmptyCharLit

ADR-0071: empty char literal ('').

UnterminatedCharLit

ADR-0071: char literal not closed before end of line or end of file.

MultiCharLit

ADR-0071: char literal contains more than one Unicode scalar.

InvalidCharEscape

ADR-0071: invalid escape sequence inside a char literal.

InvalidUnicodeEscape

ADR-0071: \u{...} malformed or value not a valid Unicode scalar.

UnexpectedToken

Fields

expected: Cow<'static, str>

found: Cow<'static, str>

UnexpectedEof

Fields

expected: Cow<'static, str>

ParseError(String)

A custom parse error with a specific message.

Used for parser-generated errors that don’t fit the “expected X, found Y” pattern.

CFfi(String)

ADR-0085: any C-FFI-related diagnostic that doesn’t have its own specific variant. Holds a free-form message; specific shapes (LinkExternDuplicateImport, FfiTypeNotAllowed, etc.) get dedicated variants as the surface grows.

NoMainFunction

UndefinedVariable(String)

UndefinedFunction(String)

AssignToImmutable(String)

UnknownType(String)

UseAfterMove(String)

Use of a value after it has been moved.

CannotMoveField

Attempt to move a non-copy field out of a struct (banned by ADR-0036).

Fields

type_name: String

field: String

TypeMismatch

Fields

expected: String

found: String

WrongArgumentCount

Fields

expected: usize

found: usize

MissingFields(Box<MissingFieldsError>)

UnknownField

Fields

struct_name: String

field_name: String

PrivateField

ADR-0072: access to a private field of a synthetic builtin struct from outside that builtin’s own methods.

Fields

struct_name: String

field_name: String

DuplicateField

Fields

struct_name: String

field_name: String

MissingFieldInDestructure

Missing field in struct destructuring pattern

Fields

struct_name: String

field: String

EmptyStruct

Anonymous struct with no fields is not allowed

EmptyAnonEnum

Anonymous enum with no variants is not allowed

ReservedTypeName

User-defined type collides with a built-in type name

Fields

type_name: String

DuplicateTypeDefinition

Duplicate type definition

Fields

type_name: String

LinearValueNotConsumed(String)

Linear value was not consumed before going out of scope

LinearStructCopy(String)

Linear struct cannot derive Copy

LinearStructClone(String)

Linear struct cannot derive Clone (ADR-0065)

CloneStructNonCopyField(Box<CloneStructNonCopyFieldError>)

@derive(Clone) v1 limitation: every field must be Copy.

PostureMismatch(Box<PostureMismatchError>)

Declared posture is inconsistent with members’ postures (ADR-0080).

UnknownDirective

A directive name that is not in the recognized set (ADR-0075). note carries either a near-match suggestion or a retirement pointer (for @handle and @copy).

Fields

name: String

note: Option<String>

UnknownMarker

@mark(...) carries a marker name not in BUILTIN_MARKERS (ADR-0083).

Fields

name: String

note: Option<String>

MarkerNotApplicable

@mark(...) carries a marker that is not applicable to the host item kind (ADR-0083).

Fields

marker: String

item_kind: &'static str

ConflictingThreadSafetyMarkers

More than one thread-safety marker on the same type (ADR-0084). At most one of unsend, checked_send, checked_sync is allowed.

Fields

type_name: String

SpawnArgNotSend

@spawn(fn, arg) argument has type that is not at least Send on the trichotomy (ADR-0084).

Fields

arg_type: String

SpawnReturnNotSend

@spawn(fn, _) return type is not at least Send (ADR-0084).

Fields

fn_name: String

ret_type: String

SpawnArgIsRef

@spawn(fn, arg) argument is a Ref(T) or MutRef(T) — references are scope-bound and cannot outlive the caller’s frame.

Fields

arg_type: String

SpawnArgIsLinear

@spawn(fn, arg) argument is a Linear type — linearity is a per-thread property today.

Fields

arg_type: String

SpawnFunctionWrongArity

@spawn(fn, _) function has wrong arity. v1 only supports single-argument workers; tuple-wrap multiple values on the caller’s side.

Fields

fn_name: String

arity: usize

SpawnFunctionNotFound

@spawn(fn, _) function name does not resolve to a top-level function. Methods, anonymous functions, and comptime-bound values are not supported in v1.

Fields

name: String

DuplicateMethod

Duplicate method definition in impl blocks for the same type

Fields

type_name: String

method_name: String

DeriveDirectFieldAccess

A derive body uses direct field projection (self.field) instead of @field(self, "name"). The host type’s structure is not known at derive-definition time (ADR-0058), so direct projection is rejected.

Fields

derive_name: String

method_name: String

DeriveNotADerive

@derive(N) references a name that is not a derive item.

Fields

name: String

The name in the @derive(...) directive.

found: String

What name actually resolved to (e.g., “struct”, “enum”, “function”, or “unknown name”).

UndefinedMethod

Method not found on a type

Fields

type_name: String

method_name: String

UndefinedAssocFn

Associated function not found on a type

Fields

type_name: String

function_name: String

MethodCallOnNonStruct

Method call on non-struct type

Fields

found: String

method_name: String

MethodCalledAsAssocFn

Calling a method (with self) as an associated function

Fields

type_name: String

method_name: String

AssocFnCalledAsMethod

Calling an associated function (without self) as a method

Fields

type_name: String

function_name: String

DuplicateDestructor

Duplicate destructor for the same type

Fields

type_name: String

DestructorUnknownType

Destructor for unknown type

Fields

type_name: String

InvalidInlineDrop

Inline fn __drop(self) is invalid on this type (wrong signature, @derive(Copy), linear, etc). ADR-0053.

Fields

type_name: String

reason: String

DuplicateConstant

Duplicate constant declaration

Fields

name: String

kind: String

ConstExprNotSupported

Expression not supported in const context

Fields

expr_kind: String

DuplicateVariant

Fields

enum_name: String

variant_name: String

UnknownVariant

Fields

enum_name: String

variant_name: String

UnknownEnumType(String)

FieldWrongOrder(Box<FieldWrongOrderError>)

FieldAccessOnNonStruct

Fields

found: String

InvalidAssignmentTarget

InoutNonLvalue

Inout argument is not an lvalue (variable, field, or array element)

InoutExclusiveAccess

Same variable passed to multiple inout parameters in a single call

Fields

variable: String

BorrowNonLvalue

Borrow argument is not an lvalue (variable, field, or array element)

MutateBorrowedValue

Cannot mutate a borrowed value

Fields

variable: String

MoveOutOfBorrow

Cannot move out of a borrowed value

Fields

variable: String

BorrowInoutConflict

Same variable passed to both borrow and inout parameters (law of exclusivity)

Fields

variable: String

InoutKeywordMissing

Argument to inout parameter is missing inout keyword at call site

BorrowKeywordMissing

Argument to borrow parameter is missing borrow keyword at call site

ReferenceEscapesFunction

Reference (Ref(T) / MutRef(T)) escapes the function in which it was constructed (ADR-0062).

Fields

type_name: String

BreakOutsideLoop

BreakInConsumingForLoop

Fields

element_type: String

ContinueOutsideLoop

IntrinsicRequiresChecked(String)

UncheckedCallRequiresChecked(String)

UncheckedDestructor

ADR-0088: drop glue runs implicitly at scope exit; there is no caller checked { } to gate it, so @mark(unchecked) fn __drop is forbidden.

ExternFnMissingUnchecked

ADR-0088: an FFI import inside link_extern / static_link_extern must carry @mark(unchecked).

Fields

fn_name: String

library: String

InterfaceMethodUncheckedMismatch(Box<InterfaceMethodUncheckedMismatchError>)

ADR-0088: implementor’s is_unchecked flag on a method does not match the interface signature’s. Conformance is strict — a checked interface method may not be satisfied by an @mark(unchecked) impl, and vice versa.

NonExhaustiveMatch

Fields

missing: Vec<String>

EmptyMatch

InvalidMatchType(String)

UnknownIntrinsic(String)

IntrinsicWrongArgCount

Fields

name: String

expected: usize

found: usize

IntrinsicTypeMismatch(Box<IntrinsicTypeMismatchError>)

ImportRequiresStringLiteral

ModuleNotFound

Fields

path: String

candidates: Vec<String>

Candidates that were tried (for error message)

StdLibNotFound

PrivateMemberAccess

Fields

item_kind: String

name: String

UnknownModuleMember

Fields

module_name: String

member_name: String

LiteralOutOfRange

Fields

value: u64

ty: String

CannotNegateUnsigned(String)

ChainedComparison

IndexOnNonArray

Fields

found: String

ArrayLengthMismatch

Fields

expected: u64

found: u64

IndexOutOfBounds

Fields

index: i64

length: u64

TypeAnnotationRequired

MoveOutOfIndex

Cannot move non-Copy element out of array index position

Fields

element_type: String

LinkError(String)

UnsupportedTarget(String)

PreviewFeatureRequired

Fields

feature: PreviewFeature

what: String

InterfaceMethodMissing(Box<InterfaceMethodMissingData>)

Type does not provide a method required by an interface.

InterfaceMethodSignatureMismatch(Box<InterfaceMethodSignatureMismatchData>)

Type provides a method but with a signature that does not match the interface requirement.

RefutablePatternInLet

ComptimeEvaluationFailed

Fields

reason: String

ComptimeArgNotConst

Fields

param_name: String

ComptimeUserError(String)

InvalidLangItem

@lang(...) problem (ADR-0079): unknown lang-item name, wrong argument shape, duplicate binding, or use outside the prelude.

Fields

reason: String

InternalError(String)

InternalCodegenError(String)

Implementations

impl ErrorKind

pub fn code(&self) -> ErrorCode

Get the error code for this error kind.

Every error kind has a unique, stable error code that can be used for documentation lookup and searchability.

Trait Implementations

impl Clone for ErrorKind

fn clone(&self) -> ErrorKind

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ErrorKind

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

Formats the value using the given formatter.

impl Display for ErrorKind

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

Formats the value using the given formatter.

impl Error for ErrorKind

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 PartialEq for ErrorKind

fn eq(&self, other: &ErrorKind) -> 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 Eq for ErrorKind

impl StructuralPartialEq for ErrorKind