Enum emacs::ErrorKind

pub enum ErrorKind {
    Signal {
        symbol: TempValue,
        data: TempValue,
    },
    Throw {
        tag: TempValue,
        value: TempValue,
    },
    WrongTypeUserPtr {
        expected: &'static str,
    },
}

Error types generic to all Rust dynamic modules.

This list is intended to grow over time and it is not recommended to exhaustively match against it.

Variants

Signal

An error signaled by Lisp code.

Fields of Signal

symbol: TempValuedata: TempValue

Throw

A non-local exit thrown by Lisp code.

Fields of Throw

tag: TempValuevalue: TempValue

WrongTypeUserPtr

An error indicating that the given value is not a user-ptr of the expected type.

Examples:

#[defun]
fn wrap(x: i64) -> Result<RefCell<i64>> {
    Ok(RefCell::new(x))
}

#[defun]
fn wrap_f(x: f64) -> Result<RefCell<f64>> {
    Ok(RefCell::new(x))
}

#[defun]
fn unwrap(r: &RefCell<i64>) -> Result<i64> {
    Ok(*r.try_borrow()?)
}

(unwrap 7)          ; *** Eval error ***  Wrong type argument: user-ptrp, 7
(unwrap (wrap 7))   ; 7
(unwrap (wrap-f 7)) ; *** Eval error ***  Wrong type user-ptr: "expected: RefCell"

Fields of WrongTypeUserPtr

expected: &'static str

Trait Implementations

impl Debug for ErrorKind

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

Formats the value using the given formatter.

impl Display for ErrorKind

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

Formats the value using the given formatter.

impl Error for ErrorKind

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