Struct ExecError 

pub struct ExecError {
    pub message: String,
    pub span: Span,
    pub raised: Option<Box<(Arc<str>, Value)>>,
}

A failure while executing Core.

Carries a span because a language server has to survive evaluating half-written code, and because “folding at seq 41 failed” is not an answer without a location.

Fields

message: String

span: Span

raised: Option<Box<(Arc<str>, Value)>>

The value a raise failed with and that value’s type name, when this failure is one the program chose rather than a fault.

A raise is a row label (§3.2, crate::row::Effect::Raises) and try: matches on the type name, so a raise that crossed this seam as a message alone would arrive at a handler as something it could not catch — the failure would be real and the Result the program was checked against unreachable. It is on the seam rather than inside a backend for the reason every other thing here is: a stub that fails is a beck-rt facility and beck-rt may not name a backend crate (docs/19 §19.9).

Implementations

impl ExecError

pub fn new(message: impl Into<String>, span: Span) -> ExecError

pub fn raise(ty: Arc<str>, value: Value, span: Span) -> ExecError

A failure a program chose: raise Declined(…), carrying the value and its type.

pub fn raised_type(&self) -> Option<&str>

The type name this failure raised, if it raised at all.

Trait Implementations

impl Clone for ExecError

fn clone(&self) -> ExecError

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ExecError

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

Formats the value using the given formatter.

impl Display for ExecError

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

Formats the value using the given formatter.

impl Error for ExecError

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.