Enum StateError 

pub enum StateError {
    KeyNotFound {
        namespace: String,
        key: String,
    },
    UnsafeSegment {
        which: &'static str,
        value: String,
    },
    IoBackup(Error),
    IoRead(Error),
    IoWrite(Error),
    Serde(Error),
    ShapeInvalid {
        reason: String,
    },
}

Errors returned by the dispatched-layout helpers (list_dispatched, show_dispatched, reset_dispatched_with_backup).

Unlike the legacy StateStore trait methods (which return String errors), these helpers use a typed enum so callers can distinguish missing-key from I/O failure at the type level without pattern-matching on OS error codes.

Variants

KeyNotFound

The requested key does not exist in the given namespace.

Arguments

• namespace — the namespace that was searched
• key — the key that was not found

Fields

namespace: String

key: String

UnsafeSegment

A namespace or key segment failed the path-safety check.

Arguments

• which — either "namespace" or "key"
• value — the offending segment value

Fields

which: &'static str

value: String

IoBackup(Error)

A backup I/O operation (fs::copy to .bak) failed.

Wraps the underlying std::io::Error. Kept separate from StateError::IoWrite so callers know that the live file was not yet touched when this error occurs.

IoRead(Error)

A read or directory-scan operation failed.

Wraps the underlying std::io::Error. Covers fs::read_to_string, fs::read_dir, and DirEntry iteration.

IoWrite(Error)

A write or rename operation on the live file or its .tmp staging copy failed.

Wraps the underlying std::io::Error. Covers fs::write and fs::rename.

Serde(Error)

JSON serialization or deserialization failed.

Uses #[from] so ? auto-converts serde_json::Error.

ShapeInvalid

The stored JSON does not have the expected shape.

Arguments

• reason — human-readable description of the shape violation (e.g. "missing 'data' top-level field" or "data.completed_steps must be an array")

Fields

reason: String

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.

impl From<Error> for StateError

fn from(source: Error) -> Self

Converts to this type from the input type.