Enum rlua::Error

pub enum Error {
    SyntaxError {
        message: StdString,
        incomplete_input: bool,
    },
    RuntimeError(StdString),
    MemoryError(StdString),
    RecursiveMutCallback,
    CallbackDestructed,
    StackError,
    BindError,
    ToLuaConversionError {
        from: &'static str,
        to: &'static str,
        message: Option<StdString>,
    },
    FromLuaConversionError {
        from: &'static str,
        to: &'static str,
        message: Option<StdString>,
    },
    CoroutineInactive,
    UserDataTypeMismatch,
    UserDataBorrowError,
    UserDataBorrowMutError,
    MismatchedRegistryKey,
    CallbackError {
        traceback: StdString,
        cause: Arc<Error>,
    },
    ExternalError(Arc<dyn StdError + Send + Sync>),
}

Error type returned by rlua methods.

Variants

SyntaxError

Fields

message: StdString

The error message as returned by Lua.

incomplete_input: bool

true if the error can likely be fixed by appending more input to the source code.

This is useful for implementing REPLs as they can query the user for more input if this is set.

Syntax error while parsing Lua source code.

RuntimeError(StdString)

Lua runtime error, aka LUA_ERRRUN.

The Lua VM returns this error when a builtin operation is performed on incompatible types. Among other things, this includes invoking operators on wrong types (such as calling or indexing a nil value).

MemoryError(StdString)

Lua memory error, aka LUA_ERRMEM

The Lua VM returns this error when the allocator does not return the requested memory, aka it is an out-of-memory error.

RecursiveMutCallback

A mutable callback has triggered Lua code that has called the same mutable callback again.

This is an error because a mutable callback can only be borrowed mutably once.

CallbackDestructed

Either a callback or a userdata method has been called, but the callback or userdata has been destructed.

This can happen either due to to being destructed in a previous __gc, or due to being destructed from exiting a Lua::scope call.

StackError

Not enough stack space to place arguments to Lua functions or return values from callbacks.

Due to the way rlua works, it should not be directly possible to run out of stack space during normal use. The only way that this error can be triggered is if a Function is called with a huge number of arguments, or a rust callback returns a huge number of return values.

BindError

Too many arguments to Function::bind

ToLuaConversionError

Fields

from: &'static str

Name of the Rust type that could not be converted.

to: &'static str

Name of the Lua type that could not be created.

message: Option<StdString>

A message indicating why the conversion failed in more detail.

A Rust value could not be converted to a Lua value.

FromLuaConversionError

Fields

from: &'static str

Name of the Lua type that could not be converted.

to: &'static str

Name of the Rust type that could not be created.

message: Option<StdString>

A string containing more detailed error information.

A Lua value could not be converted to the expected Rust type.

CoroutineInactive

Thread::resume was called on an inactive coroutine.

A coroutine is inactive if its main function has returned or if an error has occured inside the coroutine.

Thread::status can be used to check if the coroutine can be resumed without causing this error.

UserDataTypeMismatch

An AnyUserData is not the expected type in a borrow.

This error can only happen when manually using AnyUserData, or when implementing metamethods for binary operators. Refer to the documentation of UserDataMethods for details.

UserDataBorrowError

An AnyUserData immutable borrow failed because it is already borrowed mutably.

This error can occur when a method on a UserData type calls back into Lua, which then tries to call a method on the same UserData type. Consider restructuring your API to prevent these errors.

UserDataBorrowMutError

An AnyUserData mutable borrow failed because it is already borrowed.

This error can occur when a method on a UserData type calls back into Lua, which then tries to call a method on the same UserData type. Consider restructuring your API to prevent these errors.

MismatchedRegistryKey

A RegistryKey produced from a different Lua state was used.

CallbackError

Fields

traceback: StdString

Lua call stack backtrace.

cause: Arc<Error>

Original error returned by the Rust code.

A Rust callback returned Err, raising the contained Error as a Lua error.

ExternalError(Arc<dyn StdError + Send + Sync>)

A custom error.

This can be used for returning user-defined errors from callbacks.

Returning Err(ExternalError(...)) from a Rust callback will raise the error as a Lua error. The Rust code that originally invoked the Lua code then receives a CallbackError, from which the original error (and a stack traceback) can be recovered.

Implementations

impl Error

pub fn external<T: Into<Box<dyn StdError + Send + Sync>>>(err: T) -> Error

Trait Implementations

impl Clone for Error

fn clone(&self) -> Error

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Error

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

Formats the value using the given formatter.

impl Display for Error

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

Formats the value using the given formatter.

impl Error for Error

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

The lower-level source of this error, if any.

fn backtrace(&self) -> Option<&Backtrace>

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

Returns a stack backtrace, if available, of where this error occurred.

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

impl<'lua> FromLua<'lua> for Error

fn from_lua(value: Value<'lua>, lua: Context<'lua>) -> Result<Error>

Performs the conversion.

impl<'lua> ToLua<'lua> for Error

fn to_lua(self, _: Context<'lua>) -> Result<Value<'lua>>

Performs the conversion.