Struct darling::error::Error

pub struct Error { /* fields omitted */ }

An error encountered during attribute parsing.

Given that most errors darling encounters represent code bugs in dependent crates, the internal structure of the error is deliberately opaque.

Methods

impl Error

pub fn custom<T>(msg: T) -> Error where
    T: Display, 

Creates a new error with a custom message.

pub fn duplicate_field(name: &str) -> Error

Creates a new error for a field that appears twice in the input.

pub fn missing_field(name: &str) -> Error

Creates a new error for a non-optional field that does not appear in the input.

pub fn unknown_field(name: &str) -> Error

Creates a new error for a field name that appears in the input but does not correspond to a known field.

pub fn unsupported_shape(shape: &str) -> Error

Creates a new error for a struct or variant that does not adhere to the supported shape.

pub fn unsupported_format(format: &str) -> Error

pub fn unexpected_type(ty: &str) -> Error

Creates a new error for a field which has an unexpected literal type.

pub fn unknown_value(value: &str) -> Error

Creates a new error for a value which doesn't match a set of expected literals.

pub fn too_few_items(min: usize) -> Error

Creates a new error for a list which did not get enough items to proceed.

pub fn too_many_items(max: usize) -> Error

Creates a new error when a list got more items than it supports. The max argument is the largest number of items the receiver could accept.

pub fn multiple(errors: Vec<Error>) -> Error

Bundle a set of multiple errors into a single Error instance.

Panics

This function will panic if errors.is_empty() == true.

pub fn flatten(self) -> Error

Recursively converts a tree of errors to a flattened list.

pub fn at<T>(self, location: T) -> Error where
    T: Display, 

Adds a location to the error, such as a field or variant. Locations must be added in reverse order of specificity.

pub fn len(&self) -> usize

Gets the number of individual errors in this error.

This function should never return 0, as it shouldn't be possible to construct a multi-error from an empty Vec.

Trait Implementations

impl Error for Error

fn description(&self) -> &str

A short description of the error.

fn cause(&self) -> Option<&Error>

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

impl IntoIterator for Error

type Item = Error

The type of the elements being iterated over.

type IntoIter = IntoIter

Which kind of iterator are we turning this into?

Important traits for IntoIter

impl Iterator for IntoIter type Item = Error;

fn into_iter(self) -> IntoIter

Creates an iterator from a value.

impl Display for Error

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

Formats the value using the given formatter.

impl Debug for Error

fn fmt(&self, __arg_0: &mut Formatter) -> Result<(), Error>

Formats the value using the given formatter.