Enum StateError 

#[non_exhaustive]
pub enum StateError {
    TemplateRead {
        path: PathBuf,
        source: Error,
    },
    TemplateParse {
        path: PathBuf,
        source: Error,
    },
    EmptyFieldName {
        index: usize,
    },
    DuplicateField {
        field: String,
    },
    EmptyTypeTag {
        field: String,
    },
    UnknownField {
        field: String,
    },
    MissingValue {
        field: String,
    },
    TypeMismatch {
        field: String,
        expected: &'static str,
        actual: &'static str,
    },
    FieldCountMismatch {
        expected: usize,
        actual: usize,
    },
}

A failure encountered while loading a state template or accessing a state.

StateError is non-exhaustive because later workflow features may add validation failures without forcing downstream crates to update exhaustive matches. Callers should match variants of interest and retain a fallback arm.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

TemplateRead

A JSON state template could not be read from the filesystem.

Fields

path: PathBuf

Path passed to the template loader.

source: Error

Underlying filesystem error.

TemplateParse

A state template was readable but did not contain valid JSON.

Fields

path: PathBuf

Path of the malformed template.

source: Error

Underlying JSON syntax or data-model error.

EmptyFieldName

A field definition used an empty or whitespace-only name.

Fields

index: usize

Zero-based position of the invalid field in template order.

DuplicateField

Two field definitions used the same name.

Fields

field: String

Repeated field name.

EmptyTypeTag

A field definition used an empty or whitespace-only codec type tag.

Fields

field: String

Name of the field with the invalid type tag.

UnknownField

An operation addressed a key that is absent from the template layout.

Fields

field: String

Requested field name.

MissingValue

An operation required a payload from a declared but currently empty field.

Fields

field: String

Declared field whose slot is empty.

TypeMismatch

A typed operation requested a different Rust type from the stored one.

Fields

field: String

Field on which the typed operation was attempted.

expected: &'static str

Rust type requested by the caller.

actual: &'static str

Rust type currently stored in the field.

FieldCountMismatch

A reconstructed state supplied a slot count incompatible with its template layout.

Normal state creation allocates the correct number of slots. This variant primarily protects deserialization and future storage backends from constructing structurally invalid states.

Fields

expected: usize

Number of fields declared by the template.

actual: usize

Number of payload slots supplied for the state.

Trait Implementations

impl Debug for StateError

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

Formats the value using the given formatter.

impl Display for StateError

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

Formats the value using the given formatter.

impl Error for StateError

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.