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//! The internal implementation details of OpenDAL.
//!
//! This guide explains the extension boundaries used to implement OpenDAL
//! storage services and layers. Application code should use the public
//! [`Operator`] API; the raw APIs described here can change between minor
//! releases.
//!
//! OpenDAL keeps service implementations typed until it composes them into an
//! operator:
//!
//! ```text
//! Builder -> Service -> ServiceDyn -> Servicer -> Layer stack -> Operator
//!              ^                          |
//!              +------ type erasure ------+
//! ```
//!
//! - A [`Service`] implements storage operations and reports the capabilities
//!   it provides.
//! - [`ServiceDyn`] is the object-safe boundary that erases a typed service
//!   and its operation bodies.
//! - A [`Servicer`] is the shared, type-erased service handle stored by
//!   operators and layers.
//! - A [`Layer`] wraps the service stack, the operation context, or both.
//!
//! Continue with [implementing a service][accessor] or
//! [implementing a layer][layer].
//!
//! [`Operator`]: crate::Operator
//! [`Service`]: crate::raw::Service
//! [`ServiceDyn`]: crate::raw::ServiceDyn
//! [`Servicer`]: crate::raw::Servicer
//! [`Layer`]: crate::raw::Layer

pub mod accessor;
pub mod layer;
