mirror of
https://github.com/erg-lang/erg.git
synced 2025-07-19 02:55:49 +00:00
1082 lines
41 KiB
Rust
1082 lines
41 KiB
Rust
use std::mem;
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use erg_common::set::Set;
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use erg_common::traits::{Locational, Stream};
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use erg_common::Str;
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use erg_common::{assume_unreachable, dict, fn_name, set};
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#[allow(unused_imports)]
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use erg_common::{fmt_vec, log};
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use crate::ty::constructors::*;
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use crate::ty::free::{Constraint, FreeKind, HasLevel};
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use crate::ty::typaram::TyParam;
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use crate::ty::value::ValueObj;
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use crate::ty::{HasType, Predicate, Type};
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use crate::context::{Context, Variance};
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use crate::error::{TyCheckError, TyCheckErrors, TyCheckResult};
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use crate::{feature_error, hir};
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use Type::*;
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use Variance::*;
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impl Context {
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pub const TOP_LEVEL: usize = 1;
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fn generalize_tp(&self, free: TyParam, variance: Variance, uninit: bool) -> TyParam {
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match free {
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TyParam::Type(t) => TyParam::t(self.generalize_t_inner(*t, variance, uninit)),
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TyParam::FreeVar(fv) if fv.is_generalized() => TyParam::FreeVar(fv),
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TyParam::FreeVar(fv) if fv.is_linked() => {
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let fv_mut = unsafe { fv.as_ptr().as_mut().unwrap() };
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if let FreeKind::Linked(tp) = fv_mut {
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*tp = self.generalize_tp(tp.clone(), variance, uninit);
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} else {
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assume_unreachable!()
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}
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TyParam::FreeVar(fv)
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}
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// TODO: Polymorphic generalization
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TyParam::FreeVar(fv) if fv.level() > Some(self.level) => {
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let constr = self.generalize_constraint(&fv.crack_constraint(), variance);
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fv.update_constraint(constr, true);
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fv.generalize();
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TyParam::FreeVar(fv)
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}
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TyParam::Array(tps) => TyParam::Array(
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tps.into_iter()
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.map(|tp| self.generalize_tp(tp, variance, uninit))
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.collect(),
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),
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TyParam::Tuple(tps) => TyParam::Tuple(
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tps.into_iter()
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.map(|tp| self.generalize_tp(tp, variance, uninit))
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.collect(),
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),
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TyParam::Dict(tps) => TyParam::Dict(
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tps.into_iter()
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.map(|(k, v)| {
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(
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self.generalize_tp(k, variance, uninit),
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self.generalize_tp(v, variance, uninit),
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)
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})
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.collect(),
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),
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TyParam::FreeVar(_) => free,
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other if other.has_no_unbound_var() => other,
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other => todo!("{other}"),
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}
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}
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pub(crate) fn generalize_t(&self, free_type: Type) -> Type {
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if cfg!(feature = "debug") && free_type.has_qvar() {
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panic!("{free_type} has qvars")
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}
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let maybe_unbound_t = self.generalize_t_inner(free_type, Covariant, false);
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if maybe_unbound_t.has_qvar() {
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// NOTE: `?T(<: TraitX) -> Int` should be `TraitX -> Int`
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// However, the current Erg cannot handle existential types, so it quantifies anyway
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maybe_unbound_t.quantify()
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} else {
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maybe_unbound_t
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}
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}
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/// see doc/LANG/compiler/inference.md#一般化 for details
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/// ```python
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/// generalize_t(?T) == 'T: Type
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/// generalize_t(?T(<: Nat) -> ?T) == |'T <: Nat| 'T -> 'T
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/// generalize_t(?T(<: Add(?T(<: Eq(?T(<: ...)))) -> ?T) == |'T <: Add('T)| 'T -> 'T
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/// generalize_t(?T(<: TraitX) -> Int) == TraitX -> Int // 戻り値に現れないなら量化しない
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/// ```
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fn generalize_t_inner(&self, free_type: Type, variance: Variance, uninit: bool) -> Type {
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match free_type {
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FreeVar(fv) if fv.is_linked() => {
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self.generalize_t_inner(fv.crack().clone(), variance, uninit)
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/*let fv_mut = unsafe { fv.as_ptr().as_mut().unwrap() };
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if let FreeKind::Linked(t) = fv_mut {
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*t = self.generalize_t_inner(t.clone(), variance, uninit);
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} else {
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assume_unreachable!()
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}
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Type::FreeVar(fv)*/
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}
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FreeVar(fv) if fv.is_generalized() => Type::FreeVar(fv),
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// TODO: Polymorphic generalization
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FreeVar(fv) if fv.level().unwrap() > self.level => {
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if uninit {
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// use crate::ty::free::GENERIC_LEVEL;
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// return named_free_var(fv.unbound_name().unwrap(), GENERIC_LEVEL, Constraint::Uninited);
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fv.generalize();
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return Type::FreeVar(fv);
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}
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let constr = fv.constraint().unwrap();
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if let Some((l, r)) = constr.get_sub_sup() {
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// |Int <: T <: Int| T -> T ==> Int -> Int
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if l == r {
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fv.forced_link(l);
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FreeVar(fv)
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} else if r != &Obj && self.is_class(r) && variance == Contravariant {
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// |T <: Bool| T -> Int ==> Bool -> Int
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r.clone()
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} else if l != &Never && self.is_class(l) && variance == Covariant {
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// |T :> Int| X -> T ==> X -> Int
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l.clone()
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} else {
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fv.update_constraint(
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self.generalize_constraint(&fv.crack_constraint(), variance),
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true,
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);
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fv.generalize();
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Type::FreeVar(fv)
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}
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} else {
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// ?S(: Str) => 'S
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fv.update_constraint(
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self.generalize_constraint(&fv.crack_constraint(), variance),
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true,
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);
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fv.generalize();
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Type::FreeVar(fv)
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}
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}
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Subr(mut subr) => {
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subr.non_default_params.iter_mut().for_each(|nd_param| {
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*nd_param.typ_mut() = self.generalize_t_inner(
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mem::take(nd_param.typ_mut()),
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Contravariant,
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uninit,
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);
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});
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if let Some(var_args) = &mut subr.var_params {
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*var_args.typ_mut() = self.generalize_t_inner(
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mem::take(var_args.typ_mut()),
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Contravariant,
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uninit,
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);
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}
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subr.default_params.iter_mut().for_each(|d_param| {
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*d_param.typ_mut() = self.generalize_t_inner(
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mem::take(d_param.typ_mut()),
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Contravariant,
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uninit,
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);
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});
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let return_t = self.generalize_t_inner(*subr.return_t, Covariant, uninit);
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subr_t(
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subr.kind,
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subr.non_default_params,
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subr.var_params.map(|x| *x),
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subr.default_params,
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return_t,
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)
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}
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Callable { .. } => todo!(),
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Ref(t) => ref_(self.generalize_t_inner(*t, variance, uninit)),
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RefMut { before, after } => {
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let after = after.map(|aft| self.generalize_t_inner(*aft, variance, uninit));
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ref_mut(self.generalize_t_inner(*before, variance, uninit), after)
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}
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Refinement(refine) => {
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let t = self.generalize_t_inner(*refine.t, variance, uninit);
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let preds = refine
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.preds
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.into_iter()
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.map(|pred| self.generalize_pred(pred, variance, uninit))
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.collect();
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refinement(refine.var, t, preds)
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}
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Poly { name, mut params } => {
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let params = params
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.iter_mut()
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.map(|p| self.generalize_tp(mem::take(p), variance, uninit))
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.collect::<Vec<_>>();
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poly(name, params)
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}
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Proj { lhs, rhs } => {
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let lhs = self.generalize_t_inner(*lhs, variance, uninit);
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proj(lhs, rhs)
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}
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ProjCall {
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lhs,
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attr_name,
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mut args,
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} => {
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let lhs = self.generalize_tp(*lhs, variance, uninit);
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for arg in args.iter_mut() {
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*arg = self.generalize_tp(mem::take(arg), variance, uninit);
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}
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proj_call(lhs, attr_name, args)
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}
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And(l, r) => {
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let l = self.generalize_t_inner(*l, variance, uninit);
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let r = self.generalize_t_inner(*r, variance, uninit);
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// not `self.intersection` because types are generalized
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and(l, r)
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}
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Or(l, r) => {
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let l = self.generalize_t_inner(*l, variance, uninit);
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let r = self.generalize_t_inner(*r, variance, uninit);
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// not `self.union` because types are generalized
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or(l, r)
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}
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Not(l) => not(self.generalize_t_inner(*l, variance, uninit)),
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// REVIEW: その他何でもそのまま通していいのか?
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other => other,
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}
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}
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fn generalize_constraint(&self, constraint: &Constraint, variance: Variance) -> Constraint {
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match constraint {
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Constraint::Sandwiched { sub, sup, .. } => {
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let sub = self.generalize_t_inner(sub.clone(), variance, true);
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let sup = self.generalize_t_inner(sup.clone(), variance, true);
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Constraint::new_sandwiched(sub, sup)
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}
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Constraint::TypeOf(t) => {
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let t = self.generalize_t_inner(t.clone(), variance, true);
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Constraint::new_type_of(t)
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}
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Constraint::Uninited => unreachable!(),
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}
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}
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fn generalize_pred(&self, pred: Predicate, variance: Variance, uninit: bool) -> Predicate {
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match pred {
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Predicate::Const(_) => pred,
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Predicate::Value(ValueObj::Type(mut typ)) => {
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*typ.typ_mut() =
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self.generalize_t_inner(mem::take(typ.typ_mut()), variance, uninit);
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Predicate::Value(ValueObj::Type(typ))
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}
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Predicate::Value(_) => pred,
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Predicate::Equal { lhs, rhs } => {
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let rhs = self.generalize_tp(rhs, variance, uninit);
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Predicate::eq(lhs, rhs)
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}
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Predicate::GreaterEqual { lhs, rhs } => {
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let rhs = self.generalize_tp(rhs, variance, uninit);
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Predicate::ge(lhs, rhs)
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}
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Predicate::LessEqual { lhs, rhs } => {
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let rhs = self.generalize_tp(rhs, variance, uninit);
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Predicate::le(lhs, rhs)
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}
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Predicate::NotEqual { lhs, rhs } => {
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let rhs = self.generalize_tp(rhs, variance, uninit);
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Predicate::ne(lhs, rhs)
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}
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Predicate::And(lhs, rhs) => {
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let lhs = self.generalize_pred(*lhs, variance, uninit);
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let rhs = self.generalize_pred(*rhs, variance, uninit);
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Predicate::and(lhs, rhs)
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}
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Predicate::Or(lhs, rhs) => {
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let lhs = self.generalize_pred(*lhs, variance, uninit);
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let rhs = self.generalize_pred(*rhs, variance, uninit);
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Predicate::or(lhs, rhs)
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}
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Predicate::Not(pred) => {
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let pred = self.generalize_pred(*pred, variance, uninit);
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Predicate::not(pred)
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}
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}
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}
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pub(crate) fn deref_tp(
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&self,
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tp: TyParam,
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variance: Variance,
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qnames: &Set<Str>,
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loc: &impl Locational,
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) -> TyCheckResult<TyParam> {
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match tp {
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TyParam::FreeVar(fv) if fv.is_linked() => {
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let inner = fv.unwrap_linked();
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self.deref_tp(inner, variance, &set! {}, loc)
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}
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TyParam::FreeVar(_fv) if self.level == 0 => Err(TyCheckErrors::from(
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TyCheckError::dummy_infer_error(self.cfg.input.clone(), fn_name!(), line!()),
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)),
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TyParam::Type(t) => Ok(TyParam::t(self.deref_tyvar(*t, variance, qnames, loc)?)),
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TyParam::App { name, mut args } => {
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for param in args.iter_mut() {
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*param = self.deref_tp(mem::take(param), variance, qnames, loc)?;
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}
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Ok(TyParam::App { name, args })
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}
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TyParam::BinOp { op, lhs, rhs } => {
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let lhs = self.deref_tp(*lhs, variance, qnames, loc)?;
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let rhs = self.deref_tp(*rhs, variance, qnames, loc)?;
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Ok(TyParam::BinOp {
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op,
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lhs: Box::new(lhs),
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rhs: Box::new(rhs),
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})
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}
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TyParam::UnaryOp { op, val } => {
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let val = self.deref_tp(*val, variance, qnames, loc)?;
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Ok(TyParam::UnaryOp {
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op,
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val: Box::new(val),
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})
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}
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TyParam::Array(tps) => {
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let mut new_tps = vec![];
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for tp in tps {
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new_tps.push(self.deref_tp(tp, variance, qnames, loc)?);
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}
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Ok(TyParam::Array(new_tps))
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}
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TyParam::Tuple(tps) => {
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let mut new_tps = vec![];
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for tp in tps {
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new_tps.push(self.deref_tp(tp, variance, qnames, loc)?);
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}
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Ok(TyParam::Tuple(new_tps))
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}
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TyParam::Dict(dic) => {
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let mut new_dic = dict! {};
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for (k, v) in dic.into_iter() {
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new_dic.insert(
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self.deref_tp(k, variance, qnames, loc)?,
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self.deref_tp(v, variance, qnames, loc)?,
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);
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}
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Ok(TyParam::Dict(new_dic))
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}
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TyParam::Set(set) => {
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let mut new_set = set! {};
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for v in set.into_iter() {
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new_set.insert(self.deref_tp(v, variance, qnames, loc)?);
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}
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Ok(TyParam::Set(new_set))
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}
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TyParam::Proj { .. } | TyParam::Failure if self.level == 0 => Err(TyCheckErrors::from(
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TyCheckError::dummy_infer_error(self.cfg.input.clone(), fn_name!(), line!()),
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)),
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t => Ok(t),
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}
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}
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fn deref_constraint(
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&self,
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constraint: Constraint,
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variance: Variance,
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qnames: &Set<Str>,
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loc: &impl Locational,
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) -> TyCheckResult<Constraint> {
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match constraint {
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Constraint::Sandwiched { sub, sup } => Ok(Constraint::new_sandwiched(
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self.deref_tyvar(sub, variance, qnames, loc)?,
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self.deref_tyvar(sup, variance, qnames, loc)?,
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)),
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Constraint::TypeOf(t) => Ok(Constraint::new_type_of(
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self.deref_tyvar(t, variance, qnames, loc)?,
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)),
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_ => unreachable!(),
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}
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}
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fn validate_subsup(
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&self,
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sub_t: Type,
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super_t: Type,
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variance: Variance,
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qnames: &Set<Str>,
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loc: &impl Locational,
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) -> TyCheckResult<Type> {
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// TODO: Subr, ...
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match (sub_t, super_t) {
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// See tests\should_err\subtyping.er:8~13
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(
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Type::Poly {
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name: ln,
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params: lps,
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},
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Type::Poly {
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name: rn,
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params: rps,
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},
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) if ln == rn => {
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let typ = poly(ln, lps.clone());
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let (_, ctx) = self.get_nominal_type_ctx(&typ).ok_or_else(|| {
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TyCheckError::type_not_found(
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self.cfg.input.clone(),
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line!() as usize,
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loc.loc(),
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self.caused_by(),
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&typ,
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)
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})?;
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let variances = ctx.type_params_variance();
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let mut tps = vec![];
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for ((lp, rp), variance) in lps
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.into_iter()
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.zip(rps.into_iter())
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.zip(variances.into_iter())
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{
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self.sub_unify_tp(&lp, &rp, Some(variance), loc, false)?;
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let param = if variance == Covariant { lp } else { rp };
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tps.push(param);
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}
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Ok(poly(rn, tps))
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}
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(sub_t, super_t) => self.validate_simple_subsup(sub_t, super_t, variance, qnames, loc),
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}
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}
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fn validate_simple_subsup(
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&self,
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sub_t: Type,
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super_t: Type,
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variance: Variance,
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qnames: &Set<Str>,
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loc: &impl Locational,
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) -> TyCheckResult<Type> {
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if self.is_trait(&super_t) {
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self.check_trait_impl(&sub_t, &super_t, &set! {}, loc)?;
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}
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// REVIEW: Even if type constraints can be satisfied, implementation may not exist
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if self.subtype_of(&sub_t, &super_t) {
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let sub_t = if cfg!(feature = "debug") {
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sub_t
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} else {
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self.deref_tyvar(sub_t, variance, qnames, loc)?
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};
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let super_t = if cfg!(feature = "debug") {
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super_t
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} else {
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self.deref_tyvar(super_t, variance, qnames, loc)?
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};
|
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match variance {
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Variance::Covariant => Ok(sub_t),
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Variance::Contravariant => Ok(super_t),
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Variance::Invariant => {
|
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// need to check if sub_t == super_t
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if self.supertype_of(&sub_t, &super_t) {
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Ok(sub_t)
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} else {
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Err(TyCheckErrors::from(TyCheckError::subtyping_error(
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self.cfg.input.clone(),
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line!() as usize,
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&sub_t,
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&super_t,
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loc.loc(),
|
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self.caused_by(),
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)))
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}
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}
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}
|
|
} else {
|
|
let sub_t = if cfg!(feature = "debug") {
|
|
sub_t
|
|
} else {
|
|
self.deref_tyvar(sub_t, variance, qnames, loc)?
|
|
};
|
|
let super_t = if cfg!(feature = "debug") {
|
|
super_t
|
|
} else {
|
|
self.deref_tyvar(super_t, variance, qnames, loc)?
|
|
};
|
|
Err(TyCheckErrors::from(TyCheckError::subtyping_error(
|
|
self.cfg.input.clone(),
|
|
line!() as usize,
|
|
&sub_t,
|
|
&super_t,
|
|
loc.loc(),
|
|
self.caused_by(),
|
|
)))
|
|
}
|
|
}
|
|
|
|
/// e.g.
|
|
/// ```python
|
|
// ?T(:> Nat, <: Int)[n] ==> Nat (self.level <= n)
|
|
// ?T(:> Nat, <: Sub(?U(:> {1}))) ==> Nat
|
|
// ?T(:> Nat, <: Sub(?U(:> {1}))) -> ?U ==> |U: Type, T <: Sub(U)| T -> U
|
|
// ?T(:> Nat, <: Sub(Str)) ==> Error!
|
|
// ?T(:> {1, "a"}, <: Eq(?T(:> {1, "a"}, ...)) ==> Error!
|
|
// ```
|
|
pub(crate) fn deref_tyvar(
|
|
&self,
|
|
t: Type,
|
|
variance: Variance,
|
|
qnames: &Set<Str>,
|
|
loc: &impl Locational,
|
|
) -> TyCheckResult<Type> {
|
|
match t {
|
|
Type::FreeVar(fv) if fv.is_linked() => {
|
|
let t = fv.unwrap_linked();
|
|
self.deref_tyvar(t, variance, qnames, loc)
|
|
}
|
|
Type::FreeVar(fv)
|
|
if fv.is_generalized() && qnames.contains(&fv.unbound_name().unwrap()) =>
|
|
{
|
|
Ok(Type::FreeVar(fv))
|
|
}
|
|
// ?T(:> Nat, <: Int)[n] ==> Nat (self.level <= n)
|
|
// ?T(:> Nat, <: Sub ?U(:> {1}))[n] ==> Nat
|
|
// ?T(<: Int, :> Add(?T)) ==> Int
|
|
// ?T(:> Nat, <: Sub(Str)) ==> Error!
|
|
// ?T(:> {1, "a"}, <: Eq(?T(:> {1, "a"}, ...)) ==> Error!
|
|
Type::FreeVar(fv) if fv.constraint_is_sandwiched() => {
|
|
let (sub_t, super_t) = fv.get_subsup().unwrap();
|
|
if self.level <= fv.level().unwrap() {
|
|
// if fv == ?T(<: Int, :> Add(?T)), deref_tyvar(super_t) will cause infinite loop
|
|
// so we need to force linking
|
|
fv.forced_undoable_link(&sub_t);
|
|
let res = self.validate_subsup(sub_t, super_t, variance, qnames, loc);
|
|
fv.undo();
|
|
res
|
|
} else {
|
|
// no dereference at this point
|
|
// drop(constraint);
|
|
Ok(Type::FreeVar(fv))
|
|
}
|
|
}
|
|
Type::FreeVar(fv) if fv.is_unbound() => {
|
|
if self.level == 0 {
|
|
#[allow(clippy::single_match)]
|
|
match &*fv.crack_constraint() {
|
|
Constraint::TypeOf(_) => {
|
|
return Err(TyCheckErrors::from(TyCheckError::dummy_infer_error(
|
|
self.cfg.input.clone(),
|
|
fn_name!(),
|
|
line!(),
|
|
)));
|
|
}
|
|
_ => {}
|
|
}
|
|
Ok(Type::FreeVar(fv))
|
|
} else {
|
|
let new_constraint = fv.crack_constraint().clone();
|
|
let new_constraint =
|
|
self.deref_constraint(new_constraint, variance, qnames, loc)?;
|
|
fv.update_constraint(new_constraint, true);
|
|
Ok(Type::FreeVar(fv))
|
|
}
|
|
}
|
|
Type::Poly { name, mut params } => {
|
|
let typ = poly(&name, params.clone());
|
|
let (_, ctx) = self.get_nominal_type_ctx(&typ).ok_or_else(|| {
|
|
TyCheckError::type_not_found(
|
|
self.cfg.input.clone(),
|
|
line!() as usize,
|
|
loc.loc(),
|
|
self.caused_by(),
|
|
&typ,
|
|
)
|
|
})?;
|
|
let variances = ctx.type_params_variance();
|
|
for (param, variance) in params.iter_mut().zip(variances.into_iter()) {
|
|
*param = self.deref_tp(mem::take(param), variance, qnames, loc)?;
|
|
}
|
|
Ok(Type::Poly { name, params })
|
|
}
|
|
Type::Subr(mut subr) => {
|
|
for param in subr.non_default_params.iter_mut() {
|
|
*param.typ_mut() = self.deref_tyvar(
|
|
mem::take(param.typ_mut()),
|
|
variance * Contravariant,
|
|
qnames,
|
|
loc,
|
|
)?;
|
|
}
|
|
if let Some(var_args) = &mut subr.var_params {
|
|
*var_args.typ_mut() = self.deref_tyvar(
|
|
mem::take(var_args.typ_mut()),
|
|
variance * Contravariant,
|
|
qnames,
|
|
loc,
|
|
)?;
|
|
}
|
|
for d_param in subr.default_params.iter_mut() {
|
|
*d_param.typ_mut() = self.deref_tyvar(
|
|
mem::take(d_param.typ_mut()),
|
|
variance * Contravariant,
|
|
qnames,
|
|
loc,
|
|
)?;
|
|
}
|
|
subr.return_t = Box::new(self.deref_tyvar(
|
|
mem::take(&mut subr.return_t),
|
|
variance * Covariant,
|
|
qnames,
|
|
loc,
|
|
)?);
|
|
Ok(Type::Subr(subr))
|
|
}
|
|
Type::Quantified(subr) => self.eliminate_needless_quant(*subr, variance, loc),
|
|
Type::Ref(t) => {
|
|
let t = self.deref_tyvar(*t, variance, qnames, loc)?;
|
|
Ok(ref_(t))
|
|
}
|
|
Type::RefMut { before, after } => {
|
|
let before = self.deref_tyvar(*before, variance, qnames, loc)?;
|
|
let after = if let Some(after) = after {
|
|
Some(self.deref_tyvar(*after, variance, qnames, loc)?)
|
|
} else {
|
|
None
|
|
};
|
|
Ok(ref_mut(before, after))
|
|
}
|
|
// Type::Callable { .. } => todo!(),
|
|
Type::Record(mut rec) => {
|
|
for (_, field) in rec.iter_mut() {
|
|
*field = self.deref_tyvar(mem::take(field), variance, qnames, loc)?;
|
|
}
|
|
Ok(Type::Record(rec))
|
|
}
|
|
Type::Refinement(refine) => {
|
|
let t = self.deref_tyvar(*refine.t, variance, qnames, loc)?;
|
|
// TODO: deref_predicate
|
|
Ok(refinement(refine.var, t, refine.preds))
|
|
}
|
|
Type::And(l, r) => {
|
|
let l = self.deref_tyvar(*l, variance, qnames, loc)?;
|
|
let r = self.deref_tyvar(*r, variance, qnames, loc)?;
|
|
Ok(self.intersection(&l, &r))
|
|
}
|
|
Type::Or(l, r) => {
|
|
let l = self.deref_tyvar(*l, variance, qnames, loc)?;
|
|
let r = self.deref_tyvar(*r, variance, qnames, loc)?;
|
|
Ok(self.union(&l, &r))
|
|
}
|
|
Type::Not(ty) => {
|
|
let ty = self.deref_tyvar(*ty, variance, qnames, loc)?;
|
|
Ok(self.complement(&ty))
|
|
}
|
|
Type::Proj { lhs, rhs } => {
|
|
let lhs = self.deref_tyvar(*lhs, variance, qnames, loc)?;
|
|
self.eval_proj(lhs, rhs, self.level, loc)
|
|
}
|
|
Type::ProjCall {
|
|
lhs,
|
|
attr_name,
|
|
args,
|
|
} => {
|
|
let lhs = self.deref_tp(*lhs, variance, qnames, loc)?;
|
|
let mut new_args = vec![];
|
|
for arg in args.into_iter() {
|
|
new_args.push(self.deref_tp(arg, variance, qnames, loc)?);
|
|
}
|
|
self.eval_proj_call(lhs, attr_name, new_args, self.level, loc)
|
|
}
|
|
t => Ok(t),
|
|
}
|
|
}
|
|
|
|
// here ?T can be eliminated
|
|
// ?T -> Int
|
|
// ?T, ?U -> K(?U)
|
|
// Int -> ?T
|
|
// here ?T cannot be eliminated
|
|
// ?T -> ?T
|
|
// ?T -> K(?T)
|
|
// ?T -> ?U(:> ?T)
|
|
fn eliminate_needless_quant(
|
|
&self,
|
|
subr: Type,
|
|
variance: Variance,
|
|
loc: &impl Locational,
|
|
) -> TyCheckResult<Type> {
|
|
let Type::Subr(mut subr) = subr else { unreachable!() };
|
|
let essential_qnames = subr.essential_qnames();
|
|
for param in subr.non_default_params.iter_mut() {
|
|
*param.typ_mut() = self.deref_tyvar(
|
|
mem::take(param.typ_mut()),
|
|
variance * Contravariant,
|
|
&essential_qnames,
|
|
loc,
|
|
)?;
|
|
}
|
|
if let Some(var_args) = &mut subr.var_params {
|
|
*var_args.typ_mut() = self.deref_tyvar(
|
|
mem::take(var_args.typ_mut()),
|
|
variance * Contravariant,
|
|
&essential_qnames,
|
|
loc,
|
|
)?;
|
|
}
|
|
for d_param in subr.default_params.iter_mut() {
|
|
*d_param.typ_mut() = self.deref_tyvar(
|
|
mem::take(d_param.typ_mut()),
|
|
variance * Contravariant,
|
|
&essential_qnames,
|
|
loc,
|
|
)?;
|
|
}
|
|
subr.return_t = Box::new(self.deref_tyvar(
|
|
mem::take(&mut subr.return_t),
|
|
variance * Covariant,
|
|
&essential_qnames,
|
|
loc,
|
|
)?);
|
|
let subr = Type::Subr(subr);
|
|
if subr.has_qvar() {
|
|
Ok(subr.quantify())
|
|
} else {
|
|
Ok(subr)
|
|
}
|
|
}
|
|
|
|
pub fn readable_type(&self, t: Type, is_parameter: bool) -> Type {
|
|
let variance = if is_parameter {
|
|
Contravariant
|
|
} else {
|
|
Covariant
|
|
};
|
|
self.deref_tyvar(t.clone(), variance, &set! {}, &())
|
|
.unwrap_or(t)
|
|
}
|
|
|
|
pub(crate) fn trait_impl_exists(&self, class: &Type, trait_: &Type) -> bool {
|
|
// `Never` implements any trait
|
|
if self.subtype_of(class, &Type::Never) {
|
|
return true;
|
|
}
|
|
if class.is_monomorphic() {
|
|
self.mono_class_trait_impl_exist(class, trait_)
|
|
} else {
|
|
self.poly_class_trait_impl_exists(class, trait_)
|
|
}
|
|
}
|
|
|
|
fn mono_class_trait_impl_exist(&self, class: &Type, trait_: &Type) -> bool {
|
|
let mut super_exists = false;
|
|
for inst in self.get_trait_impls(trait_).into_iter() {
|
|
if self.supertype_of(&inst.sub_type, class)
|
|
&& self.supertype_of(&inst.sup_trait, trait_)
|
|
{
|
|
super_exists = true;
|
|
break;
|
|
}
|
|
}
|
|
super_exists
|
|
}
|
|
|
|
fn poly_class_trait_impl_exists(&self, class: &Type, trait_: &Type) -> bool {
|
|
let mut super_exists = false;
|
|
for inst in self.get_trait_impls(trait_).into_iter() {
|
|
if self.supertype_of(&inst.sub_type, class)
|
|
&& self.supertype_of(&inst.sup_trait, trait_)
|
|
{
|
|
super_exists = true;
|
|
break;
|
|
}
|
|
}
|
|
super_exists
|
|
}
|
|
|
|
fn check_trait_impl(
|
|
&self,
|
|
class: &Type,
|
|
trait_: &Type,
|
|
qnames: &Set<Str>,
|
|
loc: &impl Locational,
|
|
) -> TyCheckResult<()> {
|
|
if !self.trait_impl_exists(class, trait_) {
|
|
let class = if cfg!(feature = "debug") {
|
|
class.clone()
|
|
} else {
|
|
self.deref_tyvar(class.clone(), Variance::Covariant, qnames, loc)?
|
|
};
|
|
let trait_ = if cfg!(feature = "debug") {
|
|
trait_.clone()
|
|
} else {
|
|
self.deref_tyvar(trait_.clone(), Variance::Covariant, qnames, loc)?
|
|
};
|
|
Err(TyCheckErrors::from(TyCheckError::no_trait_impl_error(
|
|
self.cfg.input.clone(),
|
|
line!() as usize,
|
|
&class,
|
|
&trait_,
|
|
loc.loc(),
|
|
self.caused_by(),
|
|
self.get_simple_type_mismatch_hint(&trait_, &class),
|
|
)))
|
|
} else {
|
|
Ok(())
|
|
}
|
|
}
|
|
|
|
/// Check if all types are resolvable (if traits, check if an implementation exists)
|
|
/// And replace them if resolvable
|
|
pub(crate) fn resolve(
|
|
&mut self,
|
|
mut hir: hir::HIR,
|
|
) -> Result<hir::HIR, (hir::HIR, TyCheckErrors)> {
|
|
self.level = 0;
|
|
let mut errs = TyCheckErrors::empty();
|
|
for chunk in hir.module.iter_mut() {
|
|
if let Err(es) = self.resolve_expr_t(chunk) {
|
|
errs.extend(es);
|
|
}
|
|
}
|
|
self.resolve_ctx_vars();
|
|
if errs.is_empty() {
|
|
Ok(hir)
|
|
} else {
|
|
Err((hir, errs))
|
|
}
|
|
}
|
|
|
|
fn resolve_ctx_vars(&mut self) {
|
|
let mut locals = mem::take(&mut self.locals);
|
|
let mut params = mem::take(&mut self.params);
|
|
let mut methods_list = mem::take(&mut self.methods_list);
|
|
for (name, vi) in locals.iter_mut() {
|
|
if let Ok(t) = self.deref_tyvar(mem::take(&mut vi.t), Covariant, &set! {}, name) {
|
|
vi.t = t;
|
|
}
|
|
}
|
|
for (name, vi) in params.iter_mut() {
|
|
if let Ok(t) = self.deref_tyvar(mem::take(&mut vi.t), Covariant, &set! {}, name) {
|
|
vi.t = t;
|
|
}
|
|
}
|
|
for (_, methods) in methods_list.iter_mut() {
|
|
methods.resolve_ctx_vars();
|
|
}
|
|
self.locals = locals;
|
|
self.params = params;
|
|
self.methods_list = methods_list;
|
|
}
|
|
|
|
fn resolve_params_t(&self, params: &mut hir::Params, qnames: &Set<Str>) -> TyCheckResult<()> {
|
|
for param in params.non_defaults.iter_mut() {
|
|
param.vi.t =
|
|
self.deref_tyvar(mem::take(&mut param.vi.t), Contravariant, qnames, param)?;
|
|
}
|
|
if let Some(var_params) = &mut params.var_params {
|
|
var_params.vi.t = self.deref_tyvar(
|
|
mem::take(&mut var_params.vi.t),
|
|
Contravariant,
|
|
&set! {},
|
|
var_params.as_ref(),
|
|
)?;
|
|
}
|
|
for param in params.defaults.iter_mut() {
|
|
param.sig.vi.t =
|
|
self.deref_tyvar(mem::take(&mut param.sig.vi.t), Contravariant, qnames, param)?;
|
|
self.resolve_expr_t(&mut param.default_val)?;
|
|
}
|
|
Ok(())
|
|
}
|
|
|
|
fn resolve_expr_t(&self, expr: &mut hir::Expr) -> TyCheckResult<()> {
|
|
match expr {
|
|
hir::Expr::Lit(_) => Ok(()),
|
|
hir::Expr::Accessor(acc) => {
|
|
if !acc.ref_t().is_qvar() {
|
|
let variance = if acc.var_info().kind.is_parameter() {
|
|
Contravariant
|
|
} else {
|
|
Covariant
|
|
};
|
|
let t = mem::take(acc.ref_mut_t());
|
|
*acc.ref_mut_t() = self.deref_tyvar(t, variance, &set! {}, acc)?;
|
|
}
|
|
if let hir::Accessor::Attr(attr) = acc {
|
|
self.resolve_expr_t(&mut attr.obj)?;
|
|
}
|
|
Ok(())
|
|
}
|
|
hir::Expr::Array(array) => match array {
|
|
hir::Array::Normal(arr) => {
|
|
arr.t = self.deref_tyvar(mem::take(&mut arr.t), Covariant, &set! {}, arr)?;
|
|
for elem in arr.elems.pos_args.iter_mut() {
|
|
self.resolve_expr_t(&mut elem.expr)?;
|
|
}
|
|
Ok(())
|
|
}
|
|
hir::Array::WithLength(arr) => {
|
|
arr.t = self.deref_tyvar(mem::take(&mut arr.t), Covariant, &set! {}, arr)?;
|
|
self.resolve_expr_t(&mut arr.elem)?;
|
|
self.resolve_expr_t(&mut arr.len)?;
|
|
Ok(())
|
|
}
|
|
other => feature_error!(
|
|
TyCheckErrors,
|
|
TyCheckError,
|
|
self,
|
|
other.loc(),
|
|
"resolve types of array comprehension"
|
|
),
|
|
},
|
|
hir::Expr::Tuple(tuple) => match tuple {
|
|
hir::Tuple::Normal(tup) => {
|
|
tup.t = self.deref_tyvar(mem::take(&mut tup.t), Covariant, &set! {}, tup)?;
|
|
for elem in tup.elems.pos_args.iter_mut() {
|
|
self.resolve_expr_t(&mut elem.expr)?;
|
|
}
|
|
Ok(())
|
|
}
|
|
},
|
|
hir::Expr::Set(set) => match set {
|
|
hir::Set::Normal(st) => {
|
|
st.t = self.deref_tyvar(mem::take(&mut st.t), Covariant, &set! {}, st)?;
|
|
for elem in st.elems.pos_args.iter_mut() {
|
|
self.resolve_expr_t(&mut elem.expr)?;
|
|
}
|
|
Ok(())
|
|
}
|
|
hir::Set::WithLength(st) => {
|
|
st.t = self.deref_tyvar(mem::take(&mut st.t), Covariant, &set! {}, st)?;
|
|
self.resolve_expr_t(&mut st.elem)?;
|
|
self.resolve_expr_t(&mut st.len)?;
|
|
Ok(())
|
|
}
|
|
},
|
|
hir::Expr::Dict(dict) => match dict {
|
|
hir::Dict::Normal(dic) => {
|
|
dic.t = self.deref_tyvar(mem::take(&mut dic.t), Covariant, &set! {}, dic)?;
|
|
for kv in dic.kvs.iter_mut() {
|
|
self.resolve_expr_t(&mut kv.key)?;
|
|
self.resolve_expr_t(&mut kv.value)?;
|
|
}
|
|
Ok(())
|
|
}
|
|
other => feature_error!(
|
|
TyCheckErrors,
|
|
TyCheckError,
|
|
self,
|
|
other.loc(),
|
|
"resolve types of dict comprehension"
|
|
),
|
|
},
|
|
hir::Expr::Record(record) => {
|
|
record.t =
|
|
self.deref_tyvar(mem::take(&mut record.t), Covariant, &set! {}, record)?;
|
|
for attr in record.attrs.iter_mut() {
|
|
match &mut attr.sig {
|
|
hir::Signature::Var(var) => {
|
|
*var.ref_mut_t() = self.deref_tyvar(
|
|
mem::take(var.ref_mut_t()),
|
|
Covariant,
|
|
&set! {},
|
|
var,
|
|
)?;
|
|
}
|
|
hir::Signature::Subr(subr) => {
|
|
*subr.ref_mut_t() = self.deref_tyvar(
|
|
mem::take(subr.ref_mut_t()),
|
|
Covariant,
|
|
&set! {},
|
|
subr,
|
|
)?;
|
|
}
|
|
}
|
|
for chunk in attr.body.block.iter_mut() {
|
|
self.resolve_expr_t(chunk)?;
|
|
}
|
|
}
|
|
Ok(())
|
|
}
|
|
hir::Expr::BinOp(binop) => {
|
|
let t = mem::take(binop.signature_mut_t().unwrap());
|
|
*binop.signature_mut_t().unwrap() =
|
|
self.deref_tyvar(t, Covariant, &set! {}, binop)?;
|
|
self.resolve_expr_t(&mut binop.lhs)?;
|
|
self.resolve_expr_t(&mut binop.rhs)?;
|
|
Ok(())
|
|
}
|
|
hir::Expr::UnaryOp(unaryop) => {
|
|
let t = mem::take(unaryop.signature_mut_t().unwrap());
|
|
*unaryop.signature_mut_t().unwrap() =
|
|
self.deref_tyvar(t, Covariant, &set! {}, unaryop)?;
|
|
self.resolve_expr_t(&mut unaryop.expr)?;
|
|
Ok(())
|
|
}
|
|
hir::Expr::Call(call) => {
|
|
if let Some(t) = call.signature_mut_t() {
|
|
let t = mem::take(t);
|
|
*call.signature_mut_t().unwrap() =
|
|
self.deref_tyvar(t, Covariant, &set! {}, call)?;
|
|
}
|
|
self.resolve_expr_t(&mut call.obj)?;
|
|
for arg in call.args.pos_args.iter_mut() {
|
|
self.resolve_expr_t(&mut arg.expr)?;
|
|
}
|
|
if let Some(var_args) = &mut call.args.var_args {
|
|
self.resolve_expr_t(&mut var_args.expr)?;
|
|
}
|
|
for arg in call.args.kw_args.iter_mut() {
|
|
self.resolve_expr_t(&mut arg.expr)?;
|
|
}
|
|
Ok(())
|
|
}
|
|
hir::Expr::Def(def) => {
|
|
*def.sig.ref_mut_t() = self.deref_tyvar(
|
|
mem::take(def.sig.ref_mut_t()),
|
|
Covariant,
|
|
&set! {},
|
|
&def.sig,
|
|
)?;
|
|
let qnames = if let Type::Quantified(quant) = def.sig.ref_t() {
|
|
let Type::Subr(subr) = quant.as_ref() else { unreachable!() };
|
|
subr.essential_qnames()
|
|
} else {
|
|
set! {}
|
|
};
|
|
if let Some(params) = def.sig.params_mut() {
|
|
self.resolve_params_t(params, &qnames)?;
|
|
}
|
|
for chunk in def.body.block.iter_mut() {
|
|
self.resolve_expr_t(chunk)?;
|
|
}
|
|
Ok(())
|
|
}
|
|
hir::Expr::Lambda(lambda) => {
|
|
lambda.t =
|
|
self.deref_tyvar(mem::take(&mut lambda.t), Covariant, &set! {}, lambda)?;
|
|
let qnames = if let Type::Quantified(quant) = lambda.ref_t() {
|
|
let Type::Subr(subr) = quant.as_ref() else { unreachable!() };
|
|
subr.essential_qnames()
|
|
} else {
|
|
set! {}
|
|
};
|
|
self.resolve_params_t(&mut lambda.params, &qnames)?;
|
|
for chunk in lambda.body.iter_mut() {
|
|
self.resolve_expr_t(chunk)?;
|
|
}
|
|
Ok(())
|
|
}
|
|
hir::Expr::ClassDef(class_def) => {
|
|
for def in class_def.methods.iter_mut() {
|
|
self.resolve_expr_t(def)?;
|
|
}
|
|
Ok(())
|
|
}
|
|
hir::Expr::PatchDef(patch_def) => {
|
|
for def in patch_def.methods.iter_mut() {
|
|
self.resolve_expr_t(def)?;
|
|
}
|
|
Ok(())
|
|
}
|
|
hir::Expr::ReDef(redef) => {
|
|
// REVIEW: redef.attr is not dereferenced
|
|
for chunk in redef.block.iter_mut() {
|
|
self.resolve_expr_t(chunk)?;
|
|
}
|
|
Ok(())
|
|
}
|
|
hir::Expr::TypeAsc(tasc) => self.resolve_expr_t(&mut tasc.expr),
|
|
hir::Expr::Code(chunks) | hir::Expr::Compound(chunks) => {
|
|
for chunk in chunks.iter_mut() {
|
|
self.resolve_expr_t(chunk)?;
|
|
}
|
|
Ok(())
|
|
}
|
|
hir::Expr::Dummy(chunks) => {
|
|
for chunk in chunks.iter_mut() {
|
|
self.resolve_expr_t(chunk)?;
|
|
}
|
|
Ok(())
|
|
}
|
|
hir::Expr::Import(_) => unreachable!(),
|
|
}
|
|
}
|
|
}
|