Trait States 

pub trait States: Copy + Default {
    // Required methods
    fn index(&self) -> usize;
    fn from_index(index: usize) -> Self;
}

Trait for state types in a state machine.

Implement this trait to define the states of your DFA. Each state must be convertible to and from a unique index for efficient matrix-based lookups.

Example

use tinystate::States;

#[derive(Debug, Clone, Copy, Default)]
enum DoorState {
    #[default]
    Closed,
    Open,
    Locked,
}

impl States for DoorState {
    fn index(&self) -> usize {
        *self as usize
    }

    fn from_index(i: usize) -> Self {
        match i {
            0 => Self::Closed,
            1 => Self::Open,
            2 => Self::Locked,
            _ => unreachable!(),
        }
    }
}

Or you can use the #[derive(States)] macro to automatically do this. (Works only on unfielded enums)

Required Methods

fn index(&self) -> usize

Returns the unique index for this state.

fn from_index(index: usize) -> Self

Constructs a state from its index.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementors