Enum tvix_eval::CatchableErrorKind

pub enum CatchableErrorKind {
    Throw(Box<str>),
    AssertionFailed,
    UnimplementedFeature(Box<str>),
    NixPathResolution(Box<str>),
}

“CatchableErrorKind” errors – those which can be detected by builtins.tryEval.

Note: this type is deliberately not incorporated as a variant of ErrorKind, because then Result<Value,ErrorKind> would have redundant representations for catchable errors, which would make it too easy to handle errors incorrectly:

• Ok(Value::Catchable(cek))
• Err(ErrorKind::ThisVariantDoesNotExist(cek))

Because CatchableErrorKind is not a variant of ErrorKind, you will often see functions which return a type like:

Result<Result<T,CatchableErrorKind>,ErrorKind>

… where T is any type other than Value. This is unfortunate, because Rust’s magic ?-syntax does not work on nested Result values like this.

Variants

Throw(Box<str>)

AssertionFailed

UnimplementedFeature(Box<str>)

NixPathResolution(Box<str>)

Resolving a user-supplied angle brackets path literal failed in some way.

Trait Implementations

impl Clone for CatchableErrorKind

fn clone(&self) -> CatchableErrorKind

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for CatchableErrorKind

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

Formats the value using the given formatter.

impl Display for CatchableErrorKind

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

Formats the value using the given formatter.

impl Error for CatchableErrorKind

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

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 From<CatchableErrorKind> for Value

fn from(c: CatchableErrorKind) -> Value

Converts to this type from the input type.