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//! # FRAME
//!
//! ```no_compile
//! ______ ______ ________ ___ __ __ ______
//! /_____/\ /_____/\ /_______/\ /__//_//_/\ /_____/\
//! \::::_\/_\:::_ \ \ \::: _ \ \\::\| \| \ \\::::_\/_
//! \:\/___/\\:(_) ) )_\::(_) \ \\:. \ \\:\/___/\
//! \:::._\/ \: __ `\ \\:: __ \ \\:.\-/\ \ \\::___\/_
//! \:\ \ \ \ `\ \ \\:.\ \ \ \\. \ \ \ \\:\____/\
//! \_\/ \_\/ \_\/ \__\/\__\/ \__\/ \__\/ \_____\/
//! ```
//!
//! > **F**ramework for **R**untime **A**ggregation of **M**odularized **E**ntities: Substrate's
//! > State Transition Function (Runtime) Framework.
//!
//! ## Introduction
//!
//! As described in [`crate::reference_docs::wasm_meta_protocol`], at a high-level substrate-based blockchains are composed of two parts:
//!
//! 1. A *runtime* which represents the state transition function (i.e. "Business Logic") of a
//! blockchain, and is encoded as a Wasm blob.
//! 2. A client whose primary purpose is to execute the given runtime.
#![doc = simple_mermaid::mermaid!("../../../docs/mermaid/substrate_simple.mmd")]
//!
//! *FRAME is the Substrate's framework of choice to build a runtime.*
//!
//! FRAME is composed of two major components, **pallets** and a **runtime**.
//!
//! ## Pallets
//!
//! A pallet is a unit of encapsulated logic. It has a clearly defined responsibility and can be
//! linked to other pallets. Each pallet should try to only care about its own responsibilities and
//! make as few assumptions about the general runtime as possible. A pallet is analogous to a
//! _module_ in the runtime.
//!
//! A pallet is defined as a `mod pallet` wrapped by the [`frame::pallet`] macro. Within this macro,
//! pallet components/parts can be defined. Most notable of these parts are:
//!
//! - [Config](frame::pallet_macros::config), allowing a pallet to make itself configurable and
//! generic over types, values and such.
//! - [Storage](frame::pallet_macros::storage), allowing a pallet to define onchain storage.
//! - [Dispatchable function aka. Extrinsics](frame::pallet_macros::call), allowing a pallet to
//! define extrinsics that are callable by end users, from the outer world.
//! - [Events](frame::pallet_macros::event), allowing a pallet to emit events.
//! - [Errors](frame::pallet_macros::error), allowing a pallet to emit well-formed errors.
//!
//! Most of these components are defined using macros, the full list of which can be found in
//! [`frame::pallet_macros`].
//!
//! ### Example
//!
//! The following examples showcases a minimal pallet.
#![doc = docify::embed!("src/polkadot_sdk/frame_runtime.rs", pallet)]
//!
//!
//! A runtime is a collection of pallets that are amalgamated together. Each pallet typically has
//! some configurations (exposed as a `trait Config`) that needs to be *specified* in the runtime.
//! This is done with [`frame::runtime::prelude::construct_runtime`].
//!
//! A (real) runtime that actually wishes to compile to WASM needs to also implement a set of
//! runtime-apis. These implementation can be specified using the
//! [`frame::runtime::prelude::impl_runtime_apis`] macro.
//!
//! ### Example
//!
//! The following example shows a (test) runtime that is composing the pallet demonstrated above,
//! next to the [`frame::prelude::frame_system`] pallet, into a runtime.
#![doc = docify::embed!("src/polkadot_sdk/frame_runtime.rs", runtime)]
//!
//! ## More Examples
//!
//! You can find more FRAME examples that revolve around specific features at [`pallet_examples`].
//!
//! ## Alternatives 🌈
//!
//! There is nothing in the Substrate's client side code-base that mandates the use of FRAME. While
//! FRAME makes it very simple to write Substrate-based runtimes, it is by no means intended to be
//! the only one. At the end of the day, any WASM blob that exposes the right set of runtime APIs is
//! a valid Runtime form the point of view of a Substrate cliemt (see
//! [`crate::reference_docs::wasm_meta_protocol`]). Notable examples are:
//!
//! * writing a runtime in pure Rust, as done in [this
//! template](https://github.com/JoshOrndorff/frameless-node-template).
//! * writing a runtime in AssemblyScript,as explored in [this
//! project](https://github.com/LimeChain/subsembly).
#[cfg(test)]
mod tests {
use frame::prelude::*;
#[docify::export]
#[frame::pallet(dev_mode)]
pub mod pallet {
use super::*;
#[pallet::config]
pub trait Config: frame_system::Config {
type RuntimeEvent: IsType<<Self as frame_system::Config>::RuntimeEvent>
+ From<Event<Self>>;
}
#[pallet::pallet]
pub struct Pallet<T>(PhantomData<T>);
#[pallet::event]
pub enum Event<T: Config> {}
#[pallet::storage]
pub type Value<T> = StorageValue<Value = u32>;
#[pallet::call]
impl<T: Config> Pallet<T> {
pub fn some_dispatchable(_origin: OriginFor<T>) -> DispatchResult {
Ok(())
}
}
}
#[docify::export]
pub mod runtime {
use super::pallet as pallet_example;
use frame::{prelude::*, testing_prelude::*};
construct_runtime!(
pub struct Runtime {
System: frame_system,
Example: pallet_example,
}
);
#[derive_impl(frame_system::config_preludes::TestDefaultConfig as frame_system::DefaultConfig)]
impl frame_system::Config for Runtime {
type Block = MockBlock<Self>;
}
impl pallet_example::Config for Runtime {
type RuntimeEvent = RuntimeEvent;
}
}
}