Enum LuaError 

pub enum LuaError {
    Runtime(LuaValue),
    Syntax(LuaValue),
    RuntimeMsg(Box<[u8]>),
    SyntaxMsg(Box<[u8]>),
    Memory,
    Error,
    Yield,
    File,
    Gc,
}

The Lua error type. Carries a LuaValue payload because Lua errors can be any value (typically a string).

The *Msg variants carry the message as owned bytes instead of a GC string: host-side code builds errors with no VM (and no active heap) in scope, and allocating the payload eagerly either required an active HeapGuard or fell back to a detached, never-freed box (the issue #249 leak class — see #253). The bytes are materialized into a real GC string by into_value at the moment the error actually enters a VM, where a heap is active by construction.

Variants

Runtime(LuaValue)

Syntax(LuaValue)

RuntimeMsg(Box<[u8]>)

SyntaxMsg(Box<[u8]>)

Memory

Error

Yield

File

Gc

Implementations

impl LuaError

pub fn runtime(args: Arguments<'_>) -> LuaError

Build a runtime error whose message is owned bytes — no GC allocation happens here; into_value materializes the string when the error enters a VM (#253).

pub fn syntax(args: Arguments<'_>) -> LuaError

pub fn syntax_at(args: Arguments<'_>, source: &[u8], line: i32) -> LuaError

pub fn syntax_raw(msg: &[u8]) -> LuaError

pub fn type_error(v: &LuaValue, op: &str) -> LuaError

pub fn call_error(v: &LuaValue) -> LuaError

pub fn concat_error(p1: &LuaValue, p2: &LuaValue) -> LuaError

pub fn arith_error(p1: &LuaValue, p2: &LuaValue, _msg: &str) -> LuaError

pub fn int_overflow(_p1: &LuaValue, _p2: &LuaValue) -> LuaError

pub fn order_error(p1: &LuaValue, p2: &LuaValue) -> LuaError

pub fn for_error(v: &LuaValue, what: &str) -> LuaError

pub fn arg_error(narg: i32, msg: &str) -> LuaError

pub fn type_arg_error(narg: i32, expected: &str, got: &LuaValue) -> LuaError

pub fn from_value(v: LuaValue) -> LuaError

pub fn with_status(status: LuaStatus) -> LuaError

pub fn to_status(&self) -> LuaStatus

pub fn message_bytes(&self) -> Option<&[u8]>

The message bytes, when this error carries a textual message — either a GC string payload or the owned bytes of a not-yet- materialized *Msg variant. The canonical accessor for host-side message extraction; callers needing a fallback keep their own. Never allocates, never panics.

pub fn into_value(self) -> LuaValue

Convert the error into the Lua value that gets pushed/propagated.

This is the VM-entry boundary for the *Msg variants: the owned bytes become a real GC string here, via GcRef::new, which requires an active HeapGuard. Every in-tree call site that pushes an error object runs inside a guarded region (pcall_k, api::load, with_state, lua_resume, reset_thread), so the allocation is always collector-owned — this is what lets the guard-less detached allocation arm be removed entirely (#253).

Panics

Panics for RuntimeMsg/SyntaxMsg payloads when no HeapGuard is active. Host code that only needs the message text should use message_bytes or message_lossy instead — those never allocate and never panic.

pub fn message_lossy(&self) -> String

Human-readable error payload for embedders.

Lua errors can carry any Lua value. When the payload is a byte string, this returns it using lossy UTF-8 conversion; other payloads fall back to the Lua type name so host integrations do not have to parse Debug.

Trait Implementations

impl Clone for LuaError

fn clone(&self) -> LuaError

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for LuaError

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

Formats the value using the given formatter.

impl Display for LuaError

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

Formats the value using the given formatter.

impl Error for LuaError

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.