Attribute Macro impl_state 

#[impl_state]

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

Usage: #[impl_state]

What it does:

• Applies type-state-specific transformations to methods in an impl block,
• Enforces state requirements on methods with the #[require] macro,
• Transforms methods that transition between states using the #[switch_to] macro,
• Automatically adds the hidden _state field to the Self {} struct initialization, ensuring compliance with the type-state pattern.

Also:

• Consumes the #[require] and #[switch_to] macros and handles the necessary transformations for those macros,
• Ensures that the methods only execute in the correct state and can safely transition between valid states.