Struct StateTransitionError 

pub struct StateTransitionError<S> {
    pub from: S,
    pub to: S,
}

Error indicating an invalid state transition.

The type parameter S is the status enum (e.g. OrderStatus, ReturnStatus). This keeps transition errors strongly-typed while reusing a single generic error structure across all domain state machines.

Example

use stateset_core::errors::StateTransitionError;

#[derive(Debug, Clone, Copy, PartialEq, Eq)]
enum Light { Red, Yellow, Green }

impl std::fmt::Display for Light {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        write!(f, "{:?}", self)
    }
}

let err = StateTransitionError::new(Light::Red, Light::Green);
assert_eq!(err.to_string(), "invalid state transition from Red to Green");
assert_eq!(err.from, Light::Red);
assert_eq!(err.to, Light::Green);

Fields

from: S

The current state.

to: S

The requested (invalid) target state.

Implementations

impl<S> StateTransitionError<S>

pub const fn new(from: S, to: S) -> Self

Create a new state transition error.

Trait Implementations

impl<S: Clone> Clone for StateTransitionError<S>

fn clone(&self) -> StateTransitionError<S>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<S: Copy> Copy for StateTransitionError<S>

impl<S: Debug> Debug for StateTransitionError<S>

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

Formats the value using the given formatter.

impl<S: Display> Display for StateTransitionError<S>

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

Formats the value using the given formatter.

impl<S: Eq> Eq for StateTransitionError<S>

impl<S: Debug + Display> Error for StateTransitionError<S>

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 #99301)

Provides type-based access to context intended for error reports.

impl<S: Hash> Hash for StateTransitionError<S>

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl<S: PartialEq> PartialEq for StateTransitionError<S>

fn eq(&self, other: &StateTransitionError<S>) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl<S: PartialEq> StructuralPartialEq for StateTransitionError<S>