Trait Step 

pub trait Step<F, I, Context: ?Sized = ()>
where
    Self: Composite + Field<F>,
    <Self as Field<F>>::Child: Execute<I>,
{
    // Required method
    fn step(&mut self, instruction: &I, context: &Context) -> Result<()>;
}

Execution behavior for one composite field route and instruction type.

Available with the experimental typed-declarations feature. Use crate::field! to select a direct field or a nested route. The final child must implement Execute<I>, while the step implementation supplies the composite’s behavior, including runtime input and effect handling. crate::BuildMessage is an optional helper for preparing that input; it does not provide a step automatically. Context is shared execution input, defaults to (), and is forwarded by dispatch; the Step decides how to use it. With program-image-execution, a composite with a #[program] execution-state device supplies operand storage. Steps remain authored; program execution handles running checks and PC progression outside this trait.

Required Methods

fn step(&mut self, instruction: &I, context: &Context) -> Result<()>

Perform a step for the selected destination, borrowing its instruction.

Errors

Returns failures from preparing runtime input, executing the instruction, or handling its effects. Implementations can use ? to convert compatible execution errors into eyre::Report, including Infallible, or to propagate existing reports unchanged. Returning an error does not roll back state changes or effects already applied.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors