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use super::*;
#[derive(Debug, Clone)]
pub struct Pi {
param_ty: TermId,
result: TermId,
annot: Option<Annotation>,
code: Code,
filter: VarFilter,
flags: AtomicTyckFlags,
form: Form,
}
impl Pi {
pub fn new_unchecked(param_ty: TermId, result: TermId, annot: Option<Annotation>) -> Pi {
let code = Self::compute_code(¶m_ty, &result, annot.as_ref());
let filter = Self::compute_filter(¶m_ty, &result, annot.as_ref());
let flags = Self::compute_flags(¶m_ty, &result, annot.as_ref()).into();
let form = Self::compute_form(¶m_ty, &result);
Pi {
param_ty,
result,
annot,
code,
filter,
flags,
form,
}
}
pub fn new_typed(
param_ty: TermId,
result: TermId,
ty: Option<TermId>,
ctx: &mut (impl TyCtxMut + ?Sized),
) -> Result<Pi, Error> {
let direct = Self::new(param_ty, result, ctx.cons_ctx());
if direct.annot.is_none() {
return Err(Error::NotImplemented);
} else if ty.is_none() {
Ok(direct)
} else {
direct.coerced(ty, ctx)
}
}
pub fn new(param_ty: TermId, result: TermId, ctx: &mut (impl ConsCtx + ?Sized)) -> Pi {
let annot = if let Some(param_ty) = param_ty.universe() {
if let Some(result) = result.universe() {
Annotation::from_ty(param_ty.join(&result).into_id_with(ctx)).ok()
} else {
None
}
} else {
None
};
let result = Pi::new_unchecked(param_ty, result, annot);
debug_assert_ne!(result.flags.load_flag(GlobalTyck), L4::False);
result.flags.set_flag(LocalTyck, L4::True);
result
}
#[inline]
pub fn compute_form(param_ty: &TermId, result: &TermId) -> Form {
result.form().meet(param_ty.form()).join(Form::Head)
}
pub fn compute_code(param_ty: &TermId, result: &TermId, ty: Option<&Annotation>) -> Code {
let mut hasher = AHasher::new_with_keys(0x653, 0x5833);
let result_code = result.code();
let param_code = param_ty.code();
result_code.pure().hash(&mut hasher);
param_code.pure().hash(&mut hasher);
let pre = hasher.finish();
ty.hash(&mut hasher);
let post = hasher.finish();
Code::new(pre, post)
}
pub fn compute_filter(
param_ty: &TermId,
result: &TermId,
ty: Option<&Annotation>,
) -> VarFilter {
result
.get_filter()
.shift_down_value(result)
.union(param_ty.get_filter())
.union(ty.get_filter())
}
pub fn compute_flags(param_ty: &TermId, result: &TermId, ty: Option<&Annotation>) -> TyckFlags {
let maybe_tyck =
L4::with_false(!ty.maybe_tyck() || !param_ty.maybe_tyck() || !result.maybe_tyck());
TyckFlags::default().with_flag(TyckFlag::GlobalTyck, maybe_tyck)
}
pub fn param_ty(&self) -> &TermId {
&self.param_ty
}
pub fn result(&self) -> &TermId {
&self.result
}
pub fn unary_with(param_ty: TermId, ctx: &mut (impl ConsCtx + ?Sized)) -> Result<Pi, Error> {
let result = param_ty.shifted_id(1, 0, ctx)?;
let annot = param_ty
.universe()
.map(|u| u.into_id_with(ctx))
.and_then(|ty| Annotation::from_ty(ty).ok());
Ok(Pi::new_unchecked(param_ty, result, annot))
}
pub fn compute_local_tyck(param_ty: &TermId, result: &TermId, annot: AnnotationRef) -> bool {
if let Term::Universe(base) = &*annot.base() {
Self::compute_local_tyck_universe(param_ty, result, base.as_universe())
} else {
false
}
}
pub fn compute_local_tyck_universe(
param_ty: &TermId,
result: &TermId,
base: &Universe,
) -> bool {
(if let Some(param_ty) = param_ty.universe() {
param_ty <= *base
} else {
false
}) && (if let Some(result) = result.universe() {
result <= *base
} else {
false
})
}
pub fn local_tyck(&self, force: bool) -> TyckFlags {
let flags = self.flags.load_flags();
if !force && flags.get_flag(LocalTyck) != L4::Unknown {
return flags;
}
if let Some(annot) = &self.annot {
if Self::compute_local_tyck(&self.param_ty, &self.result, annot.borrow_annot()) {
return self.flags.set_flag(LocalTyck, L4::True);
} else {
return self.flags.set_flag(LocalTyck, L4::False);
}
} else {
debug_assert_eq!(flags.get_flag(LocalTyck), L4::False);
flags
}
}
}
impl Eq for Pi {}
impl PartialEq for Pi {
#[inline]
fn eq(&self, other: &Self) -> bool {
self.eq_in(other, &mut Structural).unwrap_or(false)
}
}
impl Hash for Pi {
#[inline]
fn hash<H: Hasher>(&self, state: &mut H) {
self.result.hash(state);
self.param_ty.hash(state);
self.annot.hash(state);
}
}
impl Cons for Pi {
type Consed = Pi;
#[inline]
fn cons(&self, ctx: &mut (impl ConsCtx + ?Sized)) -> Option<Self> {
let result = self.result.cons_id(ctx);
let param_ty = self.param_ty.cons_id(ctx);
let ty = self.annot.cons(ctx).flatten();
if result.is_none() && param_ty.is_none() && ty.is_none() {
return None;
}
let result = Pi {
param_ty: param_ty.unwrap_or_else(|| self.param_ty.clone()),
result: result.unwrap_or_else(|| self.result.clone()),
annot: ty.or_else(|| self.annot.clone()),
code: self.code,
filter: self.filter,
flags: self.flags.clone(),
form: self.form,
};
Some(result)
}
#[inline]
fn to_consed_ty(&self) -> Self::Consed {
self.clone()
}
}
impl Substitute for Pi {
type Substituted = Pi;
fn subst_rec(&self, ctx: &mut (impl SubstCtx + ?Sized)) -> Result<Option<Pi>, Error> {
if !ctx.intersects(self.filter, self.code, self.form) {
return Ok(None);
}
let param_ty = ctx.push_param(Some(&self.param_ty))?;
let result = self.result.subst_id(ctx);
ctx.pop_param()?;
let result = result?;
if param_ty.is_none() && result.is_none() {
return Ok(None);
}
let ty = self.annot.subst_rec(ctx)?;
let param_ty = param_ty.unwrap_or_else(|| self.param_ty.consed(ctx.cons_ctx()));
let result = result.unwrap_or_else(|| self.result.consed(ctx.cons_ctx()));
let ty = ty.unwrap_or_else(|| self.annot.consed(ctx.cons_ctx()));
let filter = Self::compute_filter(¶m_ty, &result, ty.as_ref());
let code = Self::compute_code(¶m_ty, &result, ty.as_ref());
let flags = Self::compute_flags(¶m_ty, &result, ty.as_ref()).into();
let form = Self::compute_form(¶m_ty, &result);
let term = Pi {
param_ty,
result,
annot: ty,
filter,
flags,
code,
form,
};
Ok(Some(term))
}
#[inline]
fn from_consed(this: Self::Consed, _ctx: &mut (impl ConsCtx + ?Sized)) -> Self::Substituted {
this
}
}
impl Typecheck for Pi {
fn do_local_tyck(&self, _ctx: &mut (impl ConsCtx + ?Sized)) -> bool {
if let Some(annot) = &self.annot {
Self::compute_local_tyck(&self.param_ty, &self.result, annot.borrow_annot())
} else {
false
}
}
fn do_global_tyck(&self, ctx: &mut (impl TyCtxMut + ?Sized)) -> Option<bool> {
if !self.param_ty.tyck(ctx)? {
return Some(false);
}
ctx.push_param(Some(&self.param_ty)).ok()?;
let result_tyck = self.result.tyck(ctx);
ctx.pop_param().ok()?;
result_tyck
}
#[inline]
fn do_annot_tyck(&self, ctx: &mut (impl TyCtxMut + ?Sized)) -> Option<bool> {
self.annot.tyck(ctx)
}
#[inline]
fn load_flags(&self) -> TyckFlags {
self.flags.load_flags()
}
#[inline]
fn set_flags(&self, flags: TyckFlags) {
self.flags.set_flags(flags);
}
}
impl HasDependencies for Pi {
#[inline]
fn has_var_dep(&self, ix: u32, equiv: bool) -> bool {
self.filter.contains(ix)
&& (self.filter.exact()
|| self.param_ty.has_var_dep(ix, equiv)
|| self.result.has_var_dep(ix + 1, equiv)
|| self.annot.has_var_dep(ix, equiv))
}
#[inline]
fn has_dep_below(&self, ix: u32, base: u32) -> bool {
if let Some(contains) = self.filter.contains_below(ix, base) {
contains
} else {
self.param_ty.has_dep_below(ix, base)
|| self.result.has_dep_below(ix + 1, base + 1)
|| self.annot.has_dep_below(ix, base)
}
}
#[inline]
fn get_filter(&self) -> VarFilter {
self.filter
}
}
impl TermEq for Pi {
#[inline]
fn eq_in(&self, other: &Self, ctx: &mut (impl TermEqCtxMut + ?Sized)) -> Option<bool> {
if let Some(result) =
ctx.approx_term_eq_code((self.code, self.form), (other.code, other.form))
{
return result;
}
let annot = if ctx.cmp_annot() {
self.annot.eq_in(&other.annot, ctx)
} else if ctx.cmp_var() {
Some(self.annot.is_some() == other.annot.is_some())
} else {
Some(true)
};
if let Some(false) = annot {
return Some(false);
}
let param_ty = self.param_ty.eq_in(&other.param_ty, ctx);
if let Some(false) = param_ty {
return Some(false);
}
let result = self.result.eq_in(&other.result, ctx);
if let Some(false) = result {
return Some(false);
}
Some(annot? && param_ty? && result?)
}
}
impl Value for Pi {
type ValueConsed = Pi;
type ValueSubstituted = Pi;
#[inline]
fn into_term_direct(self) -> Term {
Term::Pi(self)
}
#[inline]
fn annot(&self) -> Option<AnnotationRef> {
self.annot.as_ref().map(Annotation::borrow_annot)
}
#[inline]
fn id(&self) -> Option<NodeIx> {
None
}
#[inline]
fn is_local_ty(&self) -> Option<bool> {
Some(true)
}
#[inline]
fn is_local_universe(&self) -> Option<bool> {
Some(false)
}
#[inline]
fn is_local_function(&self) -> Option<bool> {
Some(true)
}
#[inline]
fn is_local_pi(&self) -> Option<bool> {
Some(true)
}
#[inline]
fn is_root(&self) -> bool {
true
}
#[inline]
fn coerce(
&self,
ty: Option<TermId>,
ctx: &mut (impl TyCtxMut + ?Sized),
) -> Result<Option<Pi>, Error> {
if let Some(annot) = &self.annot {
if let Some(ty) = ty {
if let Some(annot) = annot.coerce_ty(&ty, ctx)? {
return self.annotate_unchecked(annot, ctx.cons_ctx());
}
}
Ok(None)
} else {
let param_ty = self.param_ty.coerced(None, ctx)?;
ctx.push_param(Some(¶m_ty))?;
let result = self.result.coerced(None, ctx);
ctx.pop_param()?;
let func = Pi::new(param_ty, result?, ctx.cons_ctx());
debug_assert_eq!(func.cons(ctx.cons_ctx()), None);
Ok(Some(func))
}
}
#[inline]
fn annotate_unchecked(
&self,
annot: Annotation,
_ctx: &mut (impl ConsCtx + ?Sized),
) -> Result<Option<Pi>, Error> {
if let Some(curr_annot) = &self.annot {
if curr_annot.is_sub_annot(&annot) {
return Ok(None);
}
}
Ok(Some(Pi::new_unchecked(
self.param_ty.clone(),
self.result.clone(),
Some(annot),
)))
}
#[inline]
fn is_subtype_in(&self, other: &Term, ctx: &mut (impl TermEqCtxMut + ?Sized)) -> Option<bool> {
match other {
Term::Pi(other) => Some(
other.param_ty.is_subtype_in(&self.param_ty, ctx)?
&& self.result.is_subtype_in(&other.result, ctx)?,
),
_ if other.is_local_pi() == Some(false) => Some(false),
_ => None,
}
}
#[inline]
fn code(&self) -> Code {
self.code
}
#[inline]
fn untyped_code(&self) -> Code {
Self::compute_code(&self.param_ty, &self.result, None)
}
#[inline]
fn eq_term_in(&self, other: &Term, ctx: &mut (impl TermEqCtxMut + ?Sized)) -> Option<bool> {
match other {
Term::Pi(other) => self.eq_in(other, ctx),
_ if other.is_local_pi() == Some(false) => Some(false),
_ => None,
}
}
#[inline]
fn apply_ty(
&self,
params: &mut SmallVec<[TermId; 2]>,
ctx: &mut (impl EvalCtx + ?Sized),
) -> Result<Option<TermId>, Error> {
if let Some(param) = params.pop() {
ctx.push_subst(param)?;
let result = self.result.apply_ty(params, ctx);
ctx.pop_subst()?;
Ok(Some(result?.unwrap_or_else(|| self.result.clone())))
} else {
self.subst_id(ctx)
}
}
#[inline]
fn form(&self) -> Form {
self.form
}
}
impl PartialEq<Term> for Pi {
fn eq(&self, other: &Term) -> bool {
match other {
Term::Pi(other) => self.eq(other),
_ => false,
}
}
}
impl PartialEq<TermId> for Pi {
fn eq(&self, other: &TermId) -> bool {
self.eq(&**other)
}
}