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use super::*;
#[derive(Debug, Clone, Eq, PartialEq, Hash)]
pub enum Stmt {
Let(Let),
Join(Join),
}
#[derive(Debug, Clone, Eq, PartialEq, Hash)]
pub enum Expr {
Ident(SmolStr),
Var(u32),
App(App),
Lambda(Lambda),
Pi(Pi),
Universe(Universe),
Enum(Enum),
Variant(SmolStr),
Boolean(bool),
Natural(BigUint),
Bool,
Unit,
Case(Case),
Annotated(Annotated),
Scope(Scope),
}
#[derive(Debug, Clone, Eq, PartialEq, Hash)]
pub struct Let {
pub ident: Option<String>,
pub ty: Option<Arc<Expr>>,
pub value: Arc<Expr>,
}
#[derive(Debug, Clone, Eq, PartialEq, Hash)]
pub struct Join {
pub form: Form,
pub source: Arc<Expr>,
pub work_limit: Option<u64>,
pub target: Option<Arc<Expr>>,
}
#[derive(Debug, Clone, Eq, PartialEq, Hash)]
pub struct App(pub SmallVec<[Arc<Expr>; 2]>);
#[derive(Debug, Clone, Eq, PartialEq, Hash)]
pub struct Lambda {
pub param_name: Option<SmolStr>,
pub param_ty: Option<Arc<Expr>>,
pub result: Arc<Expr>,
}
#[derive(Debug, Clone, Eq, PartialEq, Hash)]
pub struct Pi {
pub param_name: Option<Option<SmolStr>>,
pub param_ty: Arc<Expr>,
pub result: Arc<Expr>,
}
#[derive(Debug, Copy, Clone, Eq, PartialEq, Hash)]
pub struct Universe(u32);
impl Universe {
#[inline]
pub fn try_new(level: u32, is_var: bool) -> Result<Universe, ()> {
if is_var {
Universe::try_var(level)
} else {
Universe::try_const(level)
}
}
#[inline]
pub fn try_const(level: u32) -> Result<Universe, ()> {
Ok(Universe(level.checked_mul(2).ok_or(())?))
}
#[inline]
pub fn try_var(level: u32) -> Result<Universe, ()> {
Ok(Universe(
level.checked_mul(2).ok_or(())?.checked_add(1).ok_or(())?,
))
}
#[inline]
pub fn level(self) -> u32 {
self.0 / 2
}
#[inline]
pub fn is_var(self) -> bool {
self.0 % 2 == 1
}
}
#[derive(Debug, Clone, Eq, PartialEq, Hash)]
pub struct Enum(pub Vec<SmolStr>);
#[derive(Debug, Clone, Eq, PartialEq, Hash)]
pub struct Case(pub Vec<Branch>);
#[derive(Debug, Clone, Eq, PartialEq, Hash)]
pub struct Branch {
pub pattern: Arc<Expr>,
pub result: Arc<Expr>,
}
#[derive(Debug, Clone, Eq, PartialEq, Hash)]
pub struct Annotated {
pub term: Arc<Expr>,
pub ty: Arc<Expr>,
}
#[derive(Debug, Clone, Eq, PartialEq, Hash)]
pub struct Scope {
pub stmts: Vec<Stmt>,
pub result: Arc<Expr>,
}
#[derive(Debug, Copy, Clone, Eq, PartialEq, Hash)]
pub enum Form {
Null,
Head,
Beta,
Eta,
BetaEta,
}
impl Form {
pub const fn head(self) -> bool {
use Form::*;
matches!(self, Head | Beta | BetaEta)
}
pub const fn sub(self) -> bool {
use Form::*;
matches!(self, Eta | Beta | BetaEta)
}
pub const fn eta(self) -> bool {
use Form::*;
matches!(self, Eta | BetaEta)
}
}