Crate state_shift 

state-shift is a procedural macro crate designed to:

• hide away the complexities come with type-state pattern,
• make your code more readable and maintainable,
• and still benefit from the power of type-state pattern.

Type-state is a design pattern that leverages the type system to enforce valid states and transitions at compile time. This crate provides attribute macros to transform structures and methods into type-safe stateful components, ensuring that methods are only callable in valid states, and enforcing transitions between them.

Macros:

• #[require]: Enforces that a method can only be called when the provided state is active.
• #[switch_to]: Modifies the return type of methods to switch between states.
• #[impl_state]: Defines the valid states for a given type and generates corresponding marker structs and trait implementations.
• #[type_state]: Transforms the struct into type-state compatible form, using state slots and default states.

Attribute Macros

impl_state

Modifies the methods in an impl block to work with the type-state pattern.

require

Denotes which state is required for this method to be called.

switch_to

Denotes to which state will the object transition into after this method

type_state

Turns your struct into type-state compatible version.