radn-rs/src/core.rs
2023-04-23 00:47:47 +00:00

127 lines
4.3 KiB
Rust

//! Core module for ADN functionality.
//! Brings [`Mentionable`]/[`Factory`]/[`Origin`] concepts from the original implementation in Python.
//! Allows for more generic behaviour via [`Context`], as opposed to original async-only.
mod hashing;
mod resolution;
mod serialization;
mod slice_deserializer;
mod typeless;
pub use hashing::*;
pub use resolution::*;
pub use serialization::*;
pub use slice_deserializer::*;
pub use typeless::*;
use std::{error::Error, fmt::Display, rc::Rc};
use crate::func::*;
/// Execution context.
pub trait Context {
/// Type to provide for [Monad]ic representation of computation, mostly that of resolution ([`Resolution`]).
type T: Monad;
/// Type to represent resolution errors mainly arising in [`Resolver::resolve`].
type LookupError<'a>: 'a + Error;
/// Get [type@Hash] of a slice, mostly for use in [`Point`].
fn hash(s: &[u8]) -> Hash;
}
/// Helper alias for [`WeakFunctor::F`] of [`Context::T`].
pub type Wrapped<'a, Ctx, A> = <<Ctx as Context>::T as WeakFunctor>::F<'a, A>;
/// Fundamental trait for ADN objects.
pub trait Mentionable<'a, Ctx: 'a + Context>: 'a + Serializable {
/// Type of the associated factory.
type Fctr: Factory<'a, Ctx, Mtbl = Self>;
/// Value of the associated factory.
fn factory(&self) -> Self::Fctr;
/// See implementation for the definition.
/// Hash of all the references' points concatenated, ordered, non-unique.
/// Used for walking over object trees to ensure two objects with different references don't collide.
fn topology(&self) -> Hash {
let mut vec = Vec::new();
for point in self.points_vec() {
vec.extend(point.point);
}
Ctx::hash(&vec)
}
/// References ([Point]s) to other objects.
fn points(&self, points: &mut Vec<Point<'a, Ctx, TypelessMentionable<'a, Ctx>>>);
/// [Vec] of [Point]s as used by [`Mentionable::topology`].
fn points_vec(&self) -> Vec<Point<'a, Ctx, TypelessMentionable<'a, Ctx>>> {
let mut points = Vec::new();
self.points(&mut points);
points
}
}
/// Short-hand for the type of vaalues returned by [`Factory::deserialize`].
pub type ParseResult<'a, Ctx, F> =
Result<<F as Factory<'a, Ctx>>::Mtbl, <F as Factory<'a, Ctx>>::ParseError>;
/// Trait representing deserialisation rules for [Mentionable]s.
/// Crucial for [`TypelessMentionable`] and therefore [`Mentionable::points`].
pub trait Factory<'a, Ctx: 'a + Context>: Clone + 'a {
/// Type of the associated objects.
type Mtbl: Mentionable<'a, Ctx, Fctr = Self>;
/// Type of an error that [`Factory::deserialize`] can fail with.
type ParseError: 'a + Error;
/// See [`Deserializer`], [`Resolver`].
fn deserialize(
&self,
deserializer: &mut dyn Deserializer,
resolver: Rc<dyn Resolver<'a, Ctx>>,
addresses: &mut Addresses,
) -> ParseResult<'a, Ctx, Self>;
/// Called by finite stream parsers if there's any data left.
fn unexpected_tail(&self, tail: &[u8]) -> Self::ParseError;
}
/// Represents a potentially resolvable [`Mentionable`].
pub trait Origin<'a, Ctx: 'a + Context>: 'a {
/// Type of the associated object.
type Mtbl: Mentionable<'a, Ctx>;
/// Value of the associated factory.
fn factory(&self) -> <Self::Mtbl as Mentionable<'a, Ctx>>::Fctr;
/// Try resolving the value.
fn resolve(self: Rc<Self>) -> Resolution<'a, Ctx, Self::Mtbl>;
}
/// The main way to represent a reference in ADN.
pub struct Point<'a, Ctx: 'a + Context, A: Mentionable<'a, Ctx>> {
pub point: Hash,
pub origin: Rc<dyn Origin<'a, Ctx, Mtbl = A>>,
}
impl<'a, Ctx: 'a + Context, A: Mentionable<'a, Ctx>> Clone for Point<'a, Ctx, A> {
fn clone(&self) -> Self {
Self {
point: self.point,
origin: self.origin.clone(),
}
}
}
impl<'a, Ctx: 'a + Context, A: Mentionable<'a, Ctx>> Point<'a, Ctx, A> {
/// See [`Origin::resolve`].
pub fn resolve(&self) -> Resolution<'a, Ctx, A> {
self.origin.clone().resolve()
}
}
/// Extension trait for factories.
pub trait ExtFactory<'a, Ctx: 'a + Context>: Factory<'a, Ctx> {
/// Parse the object from a slice.
fn parse_slice(
&self,
slice: &[u8],
resolver: Rc<dyn Resolver<'a, Ctx>>,
) -> ParseResult<'a, Ctx, Self>;
}