1403 lines
62 KiB
Rust
1403 lines
62 KiB
Rust
//! Type inference for expressions.
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use std::{
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collections::hash_map::Entry,
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iter::{repeat, repeat_with},
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mem,
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};
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use chalk_ir::{
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cast::Cast, fold::Shift, DebruijnIndex, GenericArgData, Mutability, TyVariableKind,
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};
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use hir_def::{
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expr::{ArithOp, Array, BinaryOp, CmpOp, Expr, ExprId, Literal, Ordering, Statement, UnaryOp},
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generics::TypeOrConstParamData,
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path::{GenericArg, GenericArgs},
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resolver::resolver_for_expr,
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ConstParamId, FieldId, FunctionId, ItemContainerId, Lookup,
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};
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use hir_expand::name::{name, Name};
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use stdx::always;
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use syntax::ast::RangeOp;
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use crate::{
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autoderef::{self, Autoderef},
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consteval,
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infer::coerce::CoerceMany,
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lower::{
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const_or_path_to_chalk, generic_arg_to_chalk, lower_to_chalk_mutability, ParamLoweringMode,
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},
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mapping::{from_chalk, ToChalk},
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method_resolution::{self, VisibleFromModule},
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primitive::{self, UintTy},
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static_lifetime, to_chalk_trait_id,
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utils::{generics, Generics},
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AdtId, Binders, CallableDefId, FnPointer, FnSig, FnSubst, Interner, Rawness, Scalar,
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Substitution, TraitRef, Ty, TyBuilder, TyExt, TyKind,
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};
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use super::{
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coerce::auto_deref_adjust_steps, find_breakable, BindingMode, BreakableContext, Diverges,
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Expectation, InferenceContext, InferenceDiagnostic, TypeMismatch,
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};
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impl<'a> InferenceContext<'a> {
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pub(crate) fn infer_expr(&mut self, tgt_expr: ExprId, expected: &Expectation) -> Ty {
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let ty = self.infer_expr_inner(tgt_expr, expected);
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if let Some(expected_ty) = expected.only_has_type(&mut self.table) {
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let could_unify = self.unify(&ty, &expected_ty);
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if !could_unify {
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self.result.type_mismatches.insert(
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tgt_expr.into(),
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TypeMismatch { expected: expected_ty, actual: ty.clone() },
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);
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}
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}
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ty
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}
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/// Infer type of expression with possibly implicit coerce to the expected type.
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/// Return the type after possible coercion.
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pub(super) fn infer_expr_coerce(&mut self, expr: ExprId, expected: &Expectation) -> Ty {
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let ty = self.infer_expr_inner(expr, expected);
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if let Some(target) = expected.only_has_type(&mut self.table) {
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match self.coerce(Some(expr), &ty, &target) {
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Ok(res) => res,
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Err(_) => {
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self.result.type_mismatches.insert(
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expr.into(),
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TypeMismatch { expected: target.clone(), actual: ty.clone() },
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);
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target
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}
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}
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} else {
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ty
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}
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}
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fn infer_expr_inner(&mut self, tgt_expr: ExprId, expected: &Expectation) -> Ty {
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self.db.unwind_if_cancelled();
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let ty = match &self.body[tgt_expr] {
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Expr::Missing => self.err_ty(),
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&Expr::If { condition, then_branch, else_branch } => {
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self.infer_expr(
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condition,
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&Expectation::has_type(TyKind::Scalar(Scalar::Bool).intern(Interner)),
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);
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let condition_diverges = mem::replace(&mut self.diverges, Diverges::Maybe);
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let mut both_arms_diverge = Diverges::Always;
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let result_ty = self.table.new_type_var();
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let then_ty = self.infer_expr_inner(then_branch, expected);
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both_arms_diverge &= mem::replace(&mut self.diverges, Diverges::Maybe);
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let mut coerce = CoerceMany::new(result_ty);
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coerce.coerce(self, Some(then_branch), &then_ty);
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let else_ty = match else_branch {
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Some(else_branch) => self.infer_expr_inner(else_branch, expected),
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None => TyBuilder::unit(),
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};
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both_arms_diverge &= self.diverges;
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// FIXME: create a synthetic `else {}` so we have something to refer to here instead of None?
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coerce.coerce(self, else_branch, &else_ty);
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self.diverges = condition_diverges | both_arms_diverge;
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coerce.complete()
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}
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&Expr::Let { pat, expr } => {
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let input_ty = self.infer_expr(expr, &Expectation::none());
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self.infer_pat(pat, &input_ty, BindingMode::default());
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TyKind::Scalar(Scalar::Bool).intern(Interner)
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}
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Expr::Block { statements, tail, label, id: _ } => {
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let old_resolver = mem::replace(
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&mut self.resolver,
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resolver_for_expr(self.db.upcast(), self.owner, tgt_expr),
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);
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let ty = match label {
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Some(_) => {
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let break_ty = self.table.new_type_var();
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self.breakables.push(BreakableContext {
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may_break: false,
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coerce: CoerceMany::new(break_ty.clone()),
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label: label.map(|label| self.body[label].name.clone()),
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});
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let ty = self.infer_block(
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tgt_expr,
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statements,
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*tail,
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&Expectation::has_type(break_ty),
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);
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let ctxt = self.breakables.pop().expect("breakable stack broken");
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if ctxt.may_break {
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ctxt.coerce.complete()
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} else {
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ty
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}
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}
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None => self.infer_block(tgt_expr, statements, *tail, expected),
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};
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self.resolver = old_resolver;
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ty
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}
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Expr::Unsafe { body } | Expr::Const { body } => self.infer_expr(*body, expected),
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Expr::TryBlock { body } => {
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let _inner = self.infer_expr(*body, expected);
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// FIXME should be std::result::Result<{inner}, _>
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self.err_ty()
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}
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Expr::Async { body } => {
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let ret_ty = self.table.new_type_var();
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let prev_diverges = mem::replace(&mut self.diverges, Diverges::Maybe);
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let prev_ret_ty = mem::replace(&mut self.return_ty, ret_ty.clone());
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let inner_ty = self.infer_expr_coerce(*body, &Expectation::has_type(ret_ty));
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self.diverges = prev_diverges;
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self.return_ty = prev_ret_ty;
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// Use the first type parameter as the output type of future.
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// existential type AsyncBlockImplTrait<InnerType>: Future<Output = InnerType>
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let impl_trait_id = crate::ImplTraitId::AsyncBlockTypeImplTrait(self.owner, *body);
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let opaque_ty_id = self.db.intern_impl_trait_id(impl_trait_id).into();
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TyKind::OpaqueType(opaque_ty_id, Substitution::from1(Interner, inner_ty))
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.intern(Interner)
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}
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Expr::Loop { body, label } => {
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self.breakables.push(BreakableContext {
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may_break: false,
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coerce: CoerceMany::new(self.table.new_type_var()),
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label: label.map(|label| self.body[label].name.clone()),
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});
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self.infer_expr(*body, &Expectation::has_type(TyBuilder::unit()));
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let ctxt = self.breakables.pop().expect("breakable stack broken");
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if ctxt.may_break {
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self.diverges = Diverges::Maybe;
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ctxt.coerce.complete()
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} else {
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TyKind::Never.intern(Interner)
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}
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}
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Expr::While { condition, body, label } => {
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self.breakables.push(BreakableContext {
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may_break: false,
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coerce: CoerceMany::new(self.err_ty()),
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label: label.map(|label| self.body[label].name.clone()),
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});
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self.infer_expr(
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*condition,
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&Expectation::has_type(TyKind::Scalar(Scalar::Bool).intern(Interner)),
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);
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self.infer_expr(*body, &Expectation::has_type(TyBuilder::unit()));
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let _ctxt = self.breakables.pop().expect("breakable stack broken");
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// the body may not run, so it diverging doesn't mean we diverge
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self.diverges = Diverges::Maybe;
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TyBuilder::unit()
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}
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Expr::For { iterable, body, pat, label } => {
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let iterable_ty = self.infer_expr(*iterable, &Expectation::none());
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self.breakables.push(BreakableContext {
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may_break: false,
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coerce: CoerceMany::new(self.err_ty()),
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label: label.map(|label| self.body[label].name.clone()),
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});
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let pat_ty =
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self.resolve_associated_type(iterable_ty, self.resolve_into_iter_item());
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self.infer_pat(*pat, &pat_ty, BindingMode::default());
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self.infer_expr(*body, &Expectation::has_type(TyBuilder::unit()));
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let _ctxt = self.breakables.pop().expect("breakable stack broken");
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// the body may not run, so it diverging doesn't mean we diverge
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self.diverges = Diverges::Maybe;
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TyBuilder::unit()
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}
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Expr::Lambda { body, args, ret_type, arg_types } => {
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assert_eq!(args.len(), arg_types.len());
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let mut sig_tys = Vec::new();
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// collect explicitly written argument types
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for arg_type in arg_types.iter() {
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let arg_ty = match arg_type {
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Some(type_ref) => self.make_ty(type_ref),
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None => self.table.new_type_var(),
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};
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sig_tys.push(arg_ty);
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}
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// add return type
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let ret_ty = match ret_type {
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Some(type_ref) => self.make_ty(type_ref),
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None => self.table.new_type_var(),
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};
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sig_tys.push(ret_ty.clone());
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let sig_ty = TyKind::Function(FnPointer {
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num_binders: 0,
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sig: FnSig { abi: (), safety: chalk_ir::Safety::Safe, variadic: false },
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substitution: FnSubst(
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Substitution::from_iter(Interner, sig_tys.clone()).shifted_in(Interner),
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),
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})
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.intern(Interner);
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let closure_id = self.db.intern_closure((self.owner, tgt_expr)).into();
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let closure_ty =
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TyKind::Closure(closure_id, Substitution::from1(Interner, sig_ty.clone()))
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.intern(Interner);
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// Eagerly try to relate the closure type with the expected
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// type, otherwise we often won't have enough information to
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// infer the body.
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self.deduce_closure_type_from_expectations(
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tgt_expr,
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&closure_ty,
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&sig_ty,
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expected,
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);
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// Now go through the argument patterns
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for (arg_pat, arg_ty) in args.iter().zip(sig_tys) {
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self.infer_pat(*arg_pat, &arg_ty, BindingMode::default());
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}
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let prev_diverges = mem::replace(&mut self.diverges, Diverges::Maybe);
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let prev_ret_ty = mem::replace(&mut self.return_ty, ret_ty.clone());
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self.infer_expr_coerce(*body, &Expectation::has_type(ret_ty));
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self.diverges = prev_diverges;
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self.return_ty = prev_ret_ty;
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closure_ty
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}
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Expr::Call { callee, args } => {
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let callee_ty = self.infer_expr(*callee, &Expectation::none());
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let mut derefs = Autoderef::new(&mut self.table, callee_ty.clone());
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let mut res = None;
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let mut derefed_callee = callee_ty.clone();
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// manual loop to be able to access `derefs.table`
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while let Some((callee_deref_ty, _)) = derefs.next() {
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res = derefs.table.callable_sig(&callee_deref_ty, args.len());
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if res.is_some() {
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derefed_callee = callee_deref_ty;
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break;
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}
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}
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// if the function is unresolved, we use is_varargs=true to
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// suppress the arg count diagnostic here
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let is_varargs =
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derefed_callee.callable_sig(self.db).map_or(false, |sig| sig.is_varargs)
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|| res.is_none();
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let (param_tys, ret_ty) = match res {
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Some(res) => {
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let adjustments = auto_deref_adjust_steps(&derefs);
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self.write_expr_adj(*callee, adjustments);
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res
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}
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None => (Vec::new(), self.err_ty()), // FIXME diagnostic
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};
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let indices_to_skip = self.check_legacy_const_generics(derefed_callee, args);
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self.register_obligations_for_call(&callee_ty);
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let expected_inputs = self.expected_inputs_for_expected_output(
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expected,
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ret_ty.clone(),
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param_tys.clone(),
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);
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self.check_call_arguments(
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tgt_expr,
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args,
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&expected_inputs,
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¶m_tys,
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&indices_to_skip,
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is_varargs,
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);
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self.normalize_associated_types_in(ret_ty)
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}
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Expr::MethodCall { receiver, args, method_name, generic_args } => self
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.infer_method_call(
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tgt_expr,
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*receiver,
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args,
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method_name,
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generic_args.as_deref(),
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expected,
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),
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Expr::Match { expr, arms } => {
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let input_ty = self.infer_expr(*expr, &Expectation::none());
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let expected = expected.adjust_for_branches(&mut self.table);
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let result_ty = if arms.is_empty() {
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TyKind::Never.intern(Interner)
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} else {
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match &expected {
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Expectation::HasType(ty) => ty.clone(),
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_ => self.table.new_type_var(),
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}
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};
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let mut coerce = CoerceMany::new(result_ty);
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let matchee_diverges = self.diverges;
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let mut all_arms_diverge = Diverges::Always;
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for arm in arms.iter() {
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self.diverges = Diverges::Maybe;
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let _pat_ty = self.infer_pat(arm.pat, &input_ty, BindingMode::default());
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if let Some(guard_expr) = arm.guard {
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self.infer_expr(
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guard_expr,
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&Expectation::has_type(TyKind::Scalar(Scalar::Bool).intern(Interner)),
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);
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}
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let arm_ty = self.infer_expr_inner(arm.expr, &expected);
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all_arms_diverge &= self.diverges;
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coerce.coerce(self, Some(arm.expr), &arm_ty);
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}
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self.diverges = matchee_diverges | all_arms_diverge;
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coerce.complete()
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}
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Expr::Path(p) => {
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// FIXME this could be more efficient...
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let resolver = resolver_for_expr(self.db.upcast(), self.owner, tgt_expr);
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self.infer_path(&resolver, p, tgt_expr.into()).unwrap_or_else(|| self.err_ty())
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}
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Expr::Continue { .. } => TyKind::Never.intern(Interner),
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Expr::Break { expr, label } => {
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let mut coerce = match find_breakable(&mut self.breakables, label.as_ref()) {
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Some(ctxt) => {
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// avoiding the borrowck
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mem::replace(
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&mut ctxt.coerce,
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CoerceMany::new(self.result.standard_types.unknown.clone()),
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)
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}
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None => CoerceMany::new(self.result.standard_types.unknown.clone()),
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};
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let val_ty = if let Some(expr) = *expr {
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self.infer_expr(expr, &Expectation::none())
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} else {
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TyBuilder::unit()
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};
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// FIXME: create a synthetic `()` during lowering so we have something to refer to here?
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coerce.coerce(self, *expr, &val_ty);
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if let Some(ctxt) = find_breakable(&mut self.breakables, label.as_ref()) {
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ctxt.coerce = coerce;
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ctxt.may_break = true;
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} else {
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self.push_diagnostic(InferenceDiagnostic::BreakOutsideOfLoop {
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expr: tgt_expr,
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});
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};
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TyKind::Never.intern(Interner)
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}
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Expr::Return { expr } => {
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if let Some(expr) = expr {
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self.infer_expr_coerce(*expr, &Expectation::has_type(self.return_ty.clone()));
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} else {
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let unit = TyBuilder::unit();
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let _ = self.coerce(Some(tgt_expr), &unit, &self.return_ty.clone());
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}
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TyKind::Never.intern(Interner)
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}
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Expr::Yield { expr } => {
|
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// FIXME: track yield type for coercion
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if let Some(expr) = expr {
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self.infer_expr(*expr, &Expectation::none());
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}
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TyKind::Never.intern(Interner)
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}
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Expr::RecordLit { path, fields, spread } => {
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let (ty, def_id) = self.resolve_variant(path.as_deref(), false);
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if let Some(variant) = def_id {
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self.write_variant_resolution(tgt_expr.into(), variant);
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}
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if let Some(t) = expected.only_has_type(&mut self.table) {
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self.unify(&ty, &t);
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}
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let substs = ty
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.as_adt()
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.map(|(_, s)| s.clone())
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.unwrap_or_else(|| Substitution::empty(Interner));
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let field_types = def_id.map(|it| self.db.field_types(it)).unwrap_or_default();
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let variant_data = def_id.map(|it| it.variant_data(self.db.upcast()));
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for field in fields.iter() {
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let field_def =
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variant_data.as_ref().and_then(|it| match it.field(&field.name) {
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Some(local_id) => Some(FieldId { parent: def_id.unwrap(), local_id }),
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None => {
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self.push_diagnostic(InferenceDiagnostic::NoSuchField {
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expr: field.expr,
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});
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None
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}
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});
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let field_ty = field_def.map_or(self.err_ty(), |it| {
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field_types[it.local_id].clone().substitute(Interner, &substs)
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});
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self.infer_expr_coerce(field.expr, &Expectation::has_type(field_ty));
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}
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if let Some(expr) = spread {
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self.infer_expr(*expr, &Expectation::has_type(ty.clone()));
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}
|
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ty
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}
|
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Expr::Field { expr, name } => {
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let receiver_ty = self.infer_expr_inner(*expr, &Expectation::none());
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|
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let mut autoderef = Autoderef::new(&mut self.table, receiver_ty);
|
|
let ty = autoderef.by_ref().find_map(|(derefed_ty, _)| {
|
|
let (field_id, parameters) = match derefed_ty.kind(Interner) {
|
|
TyKind::Tuple(_, substs) => {
|
|
return name.as_tuple_index().and_then(|idx| {
|
|
substs
|
|
.as_slice(Interner)
|
|
.get(idx)
|
|
.map(|a| a.assert_ty_ref(Interner))
|
|
.cloned()
|
|
});
|
|
}
|
|
TyKind::Adt(AdtId(hir_def::AdtId::StructId(s)), parameters) => {
|
|
let local_id = self.db.struct_data(*s).variant_data.field(name)?;
|
|
let field = FieldId { parent: (*s).into(), local_id };
|
|
(field, parameters.clone())
|
|
}
|
|
TyKind::Adt(AdtId(hir_def::AdtId::UnionId(u)), parameters) => {
|
|
let local_id = self.db.union_data(*u).variant_data.field(name)?;
|
|
let field = FieldId { parent: (*u).into(), local_id };
|
|
(field, parameters.clone())
|
|
}
|
|
_ => return None,
|
|
};
|
|
let is_visible = self.db.field_visibilities(field_id.parent)[field_id.local_id]
|
|
.is_visible_from(self.db.upcast(), self.resolver.module());
|
|
if !is_visible {
|
|
// Write down the first field resolution even if it is not visible
|
|
// This aids IDE features for private fields like goto def and in
|
|
// case of autoderef finding an applicable field, this will be
|
|
// overwritten in a following cycle
|
|
if let Entry::Vacant(entry) = self.result.field_resolutions.entry(tgt_expr)
|
|
{
|
|
entry.insert(field_id);
|
|
}
|
|
return None;
|
|
}
|
|
// can't have `write_field_resolution` here because `self.table` is borrowed :(
|
|
self.result.field_resolutions.insert(tgt_expr, field_id);
|
|
let ty = self.db.field_types(field_id.parent)[field_id.local_id]
|
|
.clone()
|
|
.substitute(Interner, ¶meters);
|
|
Some(ty)
|
|
});
|
|
let ty = match ty {
|
|
Some(ty) => {
|
|
let adjustments = auto_deref_adjust_steps(&autoderef);
|
|
self.write_expr_adj(*expr, adjustments);
|
|
let ty = self.insert_type_vars(ty);
|
|
let ty = self.normalize_associated_types_in(ty);
|
|
ty
|
|
}
|
|
_ => self.err_ty(),
|
|
};
|
|
ty
|
|
}
|
|
Expr::Await { expr } => {
|
|
let inner_ty = self.infer_expr_inner(*expr, &Expectation::none());
|
|
self.resolve_associated_type(inner_ty, self.resolve_future_future_output())
|
|
}
|
|
Expr::Try { expr } => {
|
|
let inner_ty = self.infer_expr_inner(*expr, &Expectation::none());
|
|
self.resolve_associated_type(inner_ty, self.resolve_ops_try_ok())
|
|
}
|
|
Expr::Cast { expr, type_ref } => {
|
|
// FIXME: propagate the "castable to" expectation (and find a test case that shows this is necessary)
|
|
let _inner_ty = self.infer_expr_inner(*expr, &Expectation::none());
|
|
let cast_ty = self.make_ty(type_ref);
|
|
// FIXME check the cast...
|
|
cast_ty
|
|
}
|
|
Expr::Ref { expr, rawness, mutability } => {
|
|
let mutability = lower_to_chalk_mutability(*mutability);
|
|
let expectation = if let Some((exp_inner, exp_rawness, exp_mutability)) = expected
|
|
.only_has_type(&mut self.table)
|
|
.as_ref()
|
|
.and_then(|t| t.as_reference_or_ptr())
|
|
{
|
|
if exp_mutability == Mutability::Mut && mutability == Mutability::Not {
|
|
// FIXME: record type error - expected mut reference but found shared ref,
|
|
// which cannot be coerced
|
|
}
|
|
if exp_rawness == Rawness::Ref && *rawness == Rawness::RawPtr {
|
|
// FIXME: record type error - expected reference but found ptr,
|
|
// which cannot be coerced
|
|
}
|
|
Expectation::rvalue_hint(&mut self.table, Ty::clone(exp_inner))
|
|
} else {
|
|
Expectation::none()
|
|
};
|
|
let inner_ty = self.infer_expr_inner(*expr, &expectation);
|
|
match rawness {
|
|
Rawness::RawPtr => TyKind::Raw(mutability, inner_ty),
|
|
Rawness::Ref => TyKind::Ref(mutability, static_lifetime(), inner_ty),
|
|
}
|
|
.intern(Interner)
|
|
}
|
|
&Expr::Box { expr } => self.infer_expr_box(expr, expected),
|
|
Expr::UnaryOp { expr, op } => {
|
|
let inner_ty = self.infer_expr_inner(*expr, &Expectation::none());
|
|
let inner_ty = self.resolve_ty_shallow(&inner_ty);
|
|
match op {
|
|
UnaryOp::Deref => {
|
|
autoderef::deref(&mut self.table, inner_ty).unwrap_or_else(|| self.err_ty())
|
|
}
|
|
UnaryOp::Neg => {
|
|
match inner_ty.kind(Interner) {
|
|
// Fast path for builtins
|
|
TyKind::Scalar(Scalar::Int(_) | Scalar::Uint(_) | Scalar::Float(_))
|
|
| TyKind::InferenceVar(
|
|
_,
|
|
TyVariableKind::Integer | TyVariableKind::Float,
|
|
) => inner_ty,
|
|
// Otherwise we resolve via the std::ops::Neg trait
|
|
_ => self
|
|
.resolve_associated_type(inner_ty, self.resolve_ops_neg_output()),
|
|
}
|
|
}
|
|
UnaryOp::Not => {
|
|
match inner_ty.kind(Interner) {
|
|
// Fast path for builtins
|
|
TyKind::Scalar(Scalar::Bool | Scalar::Int(_) | Scalar::Uint(_))
|
|
| TyKind::InferenceVar(_, TyVariableKind::Integer) => inner_ty,
|
|
// Otherwise we resolve via the std::ops::Not trait
|
|
_ => self
|
|
.resolve_associated_type(inner_ty, self.resolve_ops_not_output()),
|
|
}
|
|
}
|
|
}
|
|
}
|
|
Expr::BinaryOp { lhs, rhs, op } => match op {
|
|
Some(BinaryOp::Assignment { op: None }) => {
|
|
let lhs_ty = self.infer_expr(*lhs, &Expectation::none());
|
|
self.infer_expr_coerce(*rhs, &Expectation::has_type(lhs_ty));
|
|
self.result.standard_types.unit.clone()
|
|
}
|
|
Some(BinaryOp::LogicOp(_)) => {
|
|
let bool_ty = self.result.standard_types.bool_.clone();
|
|
self.infer_expr_coerce(*lhs, &Expectation::HasType(bool_ty.clone()));
|
|
let lhs_diverges = self.diverges;
|
|
self.infer_expr_coerce(*rhs, &Expectation::HasType(bool_ty.clone()));
|
|
// Depending on the LHS' value, the RHS can never execute.
|
|
self.diverges = lhs_diverges;
|
|
bool_ty
|
|
}
|
|
Some(op) => self.infer_overloadable_binop(*lhs, *op, *rhs, tgt_expr),
|
|
_ => self.err_ty(),
|
|
},
|
|
Expr::Range { lhs, rhs, range_type } => {
|
|
let lhs_ty = lhs.map(|e| self.infer_expr_inner(e, &Expectation::none()));
|
|
let rhs_expect = lhs_ty
|
|
.as_ref()
|
|
.map_or_else(Expectation::none, |ty| Expectation::has_type(ty.clone()));
|
|
let rhs_ty = rhs.map(|e| self.infer_expr(e, &rhs_expect));
|
|
match (range_type, lhs_ty, rhs_ty) {
|
|
(RangeOp::Exclusive, None, None) => match self.resolve_range_full() {
|
|
Some(adt) => TyBuilder::adt(self.db, adt).build(),
|
|
None => self.err_ty(),
|
|
},
|
|
(RangeOp::Exclusive, None, Some(ty)) => match self.resolve_range_to() {
|
|
Some(adt) => TyBuilder::adt(self.db, adt).push(ty).build(),
|
|
None => self.err_ty(),
|
|
},
|
|
(RangeOp::Inclusive, None, Some(ty)) => {
|
|
match self.resolve_range_to_inclusive() {
|
|
Some(adt) => TyBuilder::adt(self.db, adt).push(ty).build(),
|
|
None => self.err_ty(),
|
|
}
|
|
}
|
|
(RangeOp::Exclusive, Some(_), Some(ty)) => match self.resolve_range() {
|
|
Some(adt) => TyBuilder::adt(self.db, adt).push(ty).build(),
|
|
None => self.err_ty(),
|
|
},
|
|
(RangeOp::Inclusive, Some(_), Some(ty)) => {
|
|
match self.resolve_range_inclusive() {
|
|
Some(adt) => TyBuilder::adt(self.db, adt).push(ty).build(),
|
|
None => self.err_ty(),
|
|
}
|
|
}
|
|
(RangeOp::Exclusive, Some(ty), None) => match self.resolve_range_from() {
|
|
Some(adt) => TyBuilder::adt(self.db, adt).push(ty).build(),
|
|
None => self.err_ty(),
|
|
},
|
|
(RangeOp::Inclusive, _, None) => self.err_ty(),
|
|
}
|
|
}
|
|
Expr::Index { base, index } => {
|
|
let base_ty = self.infer_expr_inner(*base, &Expectation::none());
|
|
let index_ty = self.infer_expr(*index, &Expectation::none());
|
|
|
|
if let Some(index_trait) = self.resolve_ops_index() {
|
|
let canonicalized = self.canonicalize(base_ty.clone());
|
|
let receiver_adjustments = method_resolution::resolve_indexing_op(
|
|
self.db,
|
|
self.trait_env.clone(),
|
|
canonicalized.value,
|
|
index_trait,
|
|
);
|
|
let (self_ty, adj) = receiver_adjustments
|
|
.map_or((self.err_ty(), Vec::new()), |adj| {
|
|
adj.apply(&mut self.table, base_ty)
|
|
});
|
|
self.write_expr_adj(*base, adj);
|
|
self.resolve_associated_type_with_params(
|
|
self_ty,
|
|
self.resolve_ops_index_output(),
|
|
&[GenericArgData::Ty(index_ty).intern(Interner)],
|
|
)
|
|
} else {
|
|
self.err_ty()
|
|
}
|
|
}
|
|
Expr::Tuple { exprs } => {
|
|
let mut tys = match expected
|
|
.only_has_type(&mut self.table)
|
|
.as_ref()
|
|
.map(|t| t.kind(Interner))
|
|
{
|
|
Some(TyKind::Tuple(_, substs)) => substs
|
|
.iter(Interner)
|
|
.map(|a| a.assert_ty_ref(Interner).clone())
|
|
.chain(repeat_with(|| self.table.new_type_var()))
|
|
.take(exprs.len())
|
|
.collect::<Vec<_>>(),
|
|
_ => (0..exprs.len()).map(|_| self.table.new_type_var()).collect(),
|
|
};
|
|
|
|
for (expr, ty) in exprs.iter().zip(tys.iter_mut()) {
|
|
self.infer_expr_coerce(*expr, &Expectation::has_type(ty.clone()));
|
|
}
|
|
|
|
TyKind::Tuple(tys.len(), Substitution::from_iter(Interner, tys)).intern(Interner)
|
|
}
|
|
Expr::Array(array) => {
|
|
let elem_ty =
|
|
match expected.to_option(&mut self.table).as_ref().map(|t| t.kind(Interner)) {
|
|
Some(TyKind::Array(st, _) | TyKind::Slice(st)) => st.clone(),
|
|
_ => self.table.new_type_var(),
|
|
};
|
|
let mut coerce = CoerceMany::new(elem_ty.clone());
|
|
|
|
let expected = Expectation::has_type(elem_ty.clone());
|
|
let len = match array {
|
|
Array::ElementList(items) => {
|
|
for &expr in items.iter() {
|
|
let cur_elem_ty = self.infer_expr_inner(expr, &expected);
|
|
coerce.coerce(self, Some(expr), &cur_elem_ty);
|
|
}
|
|
consteval::usize_const(Some(items.len() as u64))
|
|
}
|
|
&Array::Repeat { initializer, repeat } => {
|
|
self.infer_expr_coerce(initializer, &Expectation::has_type(elem_ty));
|
|
self.infer_expr(
|
|
repeat,
|
|
&Expectation::has_type(
|
|
TyKind::Scalar(Scalar::Uint(UintTy::Usize)).intern(Interner),
|
|
),
|
|
);
|
|
|
|
if let Some(g_def) = self.owner.as_generic_def_id() {
|
|
let generics = generics(self.db.upcast(), g_def);
|
|
consteval::eval_to_const(
|
|
repeat,
|
|
ParamLoweringMode::Placeholder,
|
|
self,
|
|
|| generics,
|
|
DebruijnIndex::INNERMOST,
|
|
)
|
|
} else {
|
|
consteval::usize_const(None)
|
|
}
|
|
}
|
|
};
|
|
|
|
TyKind::Array(coerce.complete(), len).intern(Interner)
|
|
}
|
|
Expr::Literal(lit) => match lit {
|
|
Literal::Bool(..) => TyKind::Scalar(Scalar::Bool).intern(Interner),
|
|
Literal::String(..) => {
|
|
TyKind::Ref(Mutability::Not, static_lifetime(), TyKind::Str.intern(Interner))
|
|
.intern(Interner)
|
|
}
|
|
Literal::ByteString(bs) => {
|
|
let byte_type = TyKind::Scalar(Scalar::Uint(UintTy::U8)).intern(Interner);
|
|
|
|
let len = consteval::usize_const(Some(bs.len() as u64));
|
|
|
|
let array_type = TyKind::Array(byte_type, len).intern(Interner);
|
|
TyKind::Ref(Mutability::Not, static_lifetime(), array_type).intern(Interner)
|
|
}
|
|
Literal::Char(..) => TyKind::Scalar(Scalar::Char).intern(Interner),
|
|
Literal::Int(_v, ty) => match ty {
|
|
Some(int_ty) => {
|
|
TyKind::Scalar(Scalar::Int(primitive::int_ty_from_builtin(*int_ty)))
|
|
.intern(Interner)
|
|
}
|
|
None => self.table.new_integer_var(),
|
|
},
|
|
Literal::Uint(_v, ty) => match ty {
|
|
Some(int_ty) => {
|
|
TyKind::Scalar(Scalar::Uint(primitive::uint_ty_from_builtin(*int_ty)))
|
|
.intern(Interner)
|
|
}
|
|
None => self.table.new_integer_var(),
|
|
},
|
|
Literal::Float(_v, ty) => match ty {
|
|
Some(float_ty) => {
|
|
TyKind::Scalar(Scalar::Float(primitive::float_ty_from_builtin(*float_ty)))
|
|
.intern(Interner)
|
|
}
|
|
None => self.table.new_float_var(),
|
|
},
|
|
},
|
|
Expr::MacroStmts { tail } => self.infer_expr_inner(*tail, expected),
|
|
};
|
|
// use a new type variable if we got unknown here
|
|
let ty = self.insert_type_vars_shallow(ty);
|
|
self.write_expr_ty(tgt_expr, ty.clone());
|
|
if self.resolve_ty_shallow(&ty).is_never() {
|
|
// Any expression that produces a value of type `!` must have diverged
|
|
self.diverges = Diverges::Always;
|
|
}
|
|
ty
|
|
}
|
|
|
|
fn infer_expr_box(&mut self, inner_expr: ExprId, expected: &Expectation) -> Ty {
|
|
if let Some(box_id) = self.resolve_boxed_box() {
|
|
let table = &mut self.table;
|
|
let inner_exp = expected
|
|
.to_option(table)
|
|
.as_ref()
|
|
.map(|e| e.as_adt())
|
|
.flatten()
|
|
.filter(|(e_adt, _)| e_adt == &box_id)
|
|
.map(|(_, subts)| {
|
|
let g = subts.at(Interner, 0);
|
|
Expectation::rvalue_hint(table, Ty::clone(g.assert_ty_ref(Interner)))
|
|
})
|
|
.unwrap_or_else(Expectation::none);
|
|
|
|
let inner_ty = self.infer_expr_inner(inner_expr, &inner_exp);
|
|
TyBuilder::adt(self.db, box_id)
|
|
.push(inner_ty)
|
|
.fill_with_defaults(self.db, || self.table.new_type_var())
|
|
.build()
|
|
} else {
|
|
self.err_ty()
|
|
}
|
|
}
|
|
|
|
fn infer_overloadable_binop(
|
|
&mut self,
|
|
lhs: ExprId,
|
|
op: BinaryOp,
|
|
rhs: ExprId,
|
|
tgt_expr: ExprId,
|
|
) -> Ty {
|
|
let lhs_expectation = Expectation::none();
|
|
let lhs_ty = self.infer_expr(lhs, &lhs_expectation);
|
|
let rhs_ty = self.table.new_type_var();
|
|
|
|
let func = self.resolve_binop_method(op);
|
|
let func = match func {
|
|
Some(func) => func,
|
|
None => {
|
|
let rhs_ty = self.builtin_binary_op_rhs_expectation(op, lhs_ty.clone());
|
|
let rhs_ty = self.infer_expr_coerce(rhs, &Expectation::from_option(rhs_ty));
|
|
return self
|
|
.builtin_binary_op_return_ty(op, lhs_ty, rhs_ty)
|
|
.unwrap_or_else(|| self.err_ty());
|
|
}
|
|
};
|
|
|
|
let subst = TyBuilder::subst_for_def(self.db, func)
|
|
.push(lhs_ty.clone())
|
|
.push(rhs_ty.clone())
|
|
.build();
|
|
self.write_method_resolution(tgt_expr, func, subst.clone());
|
|
|
|
let method_ty = self.db.value_ty(func.into()).substitute(Interner, &subst);
|
|
self.register_obligations_for_call(&method_ty);
|
|
|
|
self.infer_expr_coerce(rhs, &Expectation::has_type(rhs_ty.clone()));
|
|
|
|
let ret_ty = match method_ty.callable_sig(self.db) {
|
|
Some(sig) => sig.ret().clone(),
|
|
None => self.err_ty(),
|
|
};
|
|
|
|
let ret_ty = self.normalize_associated_types_in(ret_ty);
|
|
|
|
// FIXME: record autoref adjustments
|
|
|
|
// use knowledge of built-in binary ops, which can sometimes help inference
|
|
if let Some(builtin_rhs) = self.builtin_binary_op_rhs_expectation(op, lhs_ty.clone()) {
|
|
self.unify(&builtin_rhs, &rhs_ty);
|
|
}
|
|
if let Some(builtin_ret) = self.builtin_binary_op_return_ty(op, lhs_ty, rhs_ty) {
|
|
self.unify(&builtin_ret, &ret_ty);
|
|
}
|
|
|
|
ret_ty
|
|
}
|
|
|
|
fn infer_block(
|
|
&mut self,
|
|
expr: ExprId,
|
|
statements: &[Statement],
|
|
tail: Option<ExprId>,
|
|
expected: &Expectation,
|
|
) -> Ty {
|
|
for stmt in statements {
|
|
match stmt {
|
|
Statement::Let { pat, type_ref, initializer, else_branch } => {
|
|
let decl_ty = type_ref
|
|
.as_ref()
|
|
.map(|tr| self.make_ty(tr))
|
|
.unwrap_or_else(|| self.err_ty());
|
|
|
|
// Always use the declared type when specified
|
|
let mut ty = decl_ty.clone();
|
|
|
|
if let Some(expr) = initializer {
|
|
let actual_ty =
|
|
self.infer_expr_coerce(*expr, &Expectation::has_type(decl_ty.clone()));
|
|
if decl_ty.is_unknown() {
|
|
ty = actual_ty;
|
|
}
|
|
}
|
|
|
|
if let Some(expr) = else_branch {
|
|
self.infer_expr_coerce(
|
|
*expr,
|
|
&Expectation::has_type(Ty::new(Interner, TyKind::Never)),
|
|
);
|
|
}
|
|
|
|
self.infer_pat(*pat, &ty, BindingMode::default());
|
|
}
|
|
Statement::Expr { expr, .. } => {
|
|
self.infer_expr(*expr, &Expectation::none());
|
|
}
|
|
}
|
|
}
|
|
|
|
if let Some(expr) = tail {
|
|
self.infer_expr_coerce(expr, expected)
|
|
} else {
|
|
// Citing rustc: if there is no explicit tail expression,
|
|
// that is typically equivalent to a tail expression
|
|
// of `()` -- except if the block diverges. In that
|
|
// case, there is no value supplied from the tail
|
|
// expression (assuming there are no other breaks,
|
|
// this implies that the type of the block will be
|
|
// `!`).
|
|
if self.diverges.is_always() {
|
|
// we don't even make an attempt at coercion
|
|
self.table.new_maybe_never_var()
|
|
} else {
|
|
if let Some(t) = expected.only_has_type(&mut self.table) {
|
|
if self.coerce(Some(expr), &TyBuilder::unit(), &t).is_err() {
|
|
self.result.type_mismatches.insert(
|
|
expr.into(),
|
|
TypeMismatch { expected: t.clone(), actual: TyBuilder::unit() },
|
|
);
|
|
}
|
|
t
|
|
} else {
|
|
TyBuilder::unit()
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
fn infer_method_call(
|
|
&mut self,
|
|
tgt_expr: ExprId,
|
|
receiver: ExprId,
|
|
args: &[ExprId],
|
|
method_name: &Name,
|
|
generic_args: Option<&GenericArgs>,
|
|
expected: &Expectation,
|
|
) -> Ty {
|
|
let receiver_ty = self.infer_expr(receiver, &Expectation::none());
|
|
let canonicalized_receiver = self.canonicalize(receiver_ty.clone());
|
|
|
|
let traits_in_scope = self.resolver.traits_in_scope(self.db.upcast());
|
|
|
|
let resolved = method_resolution::lookup_method(
|
|
&canonicalized_receiver.value,
|
|
self.db,
|
|
self.trait_env.clone(),
|
|
&traits_in_scope,
|
|
VisibleFromModule::Filter(self.resolver.module()),
|
|
method_name,
|
|
);
|
|
let (receiver_ty, method_ty, substs) = match resolved {
|
|
Some((adjust, func)) => {
|
|
let (ty, adjustments) = adjust.apply(&mut self.table, receiver_ty);
|
|
let generics = generics(self.db.upcast(), func.into());
|
|
let substs = self.substs_for_method_call(generics, generic_args);
|
|
self.write_expr_adj(receiver, adjustments);
|
|
self.write_method_resolution(tgt_expr, func, substs.clone());
|
|
(ty, self.db.value_ty(func.into()), substs)
|
|
}
|
|
None => (
|
|
receiver_ty,
|
|
Binders::empty(Interner, self.err_ty()),
|
|
Substitution::empty(Interner),
|
|
),
|
|
};
|
|
let method_ty = method_ty.substitute(Interner, &substs);
|
|
self.register_obligations_for_call(&method_ty);
|
|
let (formal_receiver_ty, param_tys, ret_ty, is_varargs) =
|
|
match method_ty.callable_sig(self.db) {
|
|
Some(sig) => {
|
|
if !sig.params().is_empty() {
|
|
(
|
|
sig.params()[0].clone(),
|
|
sig.params()[1..].to_vec(),
|
|
sig.ret().clone(),
|
|
sig.is_varargs,
|
|
)
|
|
} else {
|
|
(self.err_ty(), Vec::new(), sig.ret().clone(), sig.is_varargs)
|
|
}
|
|
}
|
|
None => (self.err_ty(), Vec::new(), self.err_ty(), true),
|
|
};
|
|
self.unify(&formal_receiver_ty, &receiver_ty);
|
|
|
|
let expected_inputs =
|
|
self.expected_inputs_for_expected_output(expected, ret_ty.clone(), param_tys.clone());
|
|
|
|
self.check_call_arguments(tgt_expr, args, &expected_inputs, ¶m_tys, &[], is_varargs);
|
|
self.normalize_associated_types_in(ret_ty)
|
|
}
|
|
|
|
fn expected_inputs_for_expected_output(
|
|
&mut self,
|
|
expected_output: &Expectation,
|
|
output: Ty,
|
|
inputs: Vec<Ty>,
|
|
) -> Vec<Ty> {
|
|
if let Some(expected_ty) = expected_output.to_option(&mut self.table) {
|
|
self.table.fudge_inference(|table| {
|
|
if table.try_unify(&expected_ty, &output).is_ok() {
|
|
table.resolve_with_fallback(inputs, &|var, kind, _, _| match kind {
|
|
chalk_ir::VariableKind::Ty(tk) => var.to_ty(Interner, tk).cast(Interner),
|
|
chalk_ir::VariableKind::Lifetime => {
|
|
var.to_lifetime(Interner).cast(Interner)
|
|
}
|
|
chalk_ir::VariableKind::Const(ty) => {
|
|
var.to_const(Interner, ty).cast(Interner)
|
|
}
|
|
})
|
|
} else {
|
|
Vec::new()
|
|
}
|
|
})
|
|
} else {
|
|
Vec::new()
|
|
}
|
|
}
|
|
|
|
fn check_call_arguments(
|
|
&mut self,
|
|
expr: ExprId,
|
|
args: &[ExprId],
|
|
expected_inputs: &[Ty],
|
|
param_tys: &[Ty],
|
|
skip_indices: &[u32],
|
|
is_varargs: bool,
|
|
) {
|
|
if args.len() != param_tys.len() + skip_indices.len() && !is_varargs {
|
|
self.push_diagnostic(InferenceDiagnostic::MismatchedArgCount {
|
|
call_expr: expr,
|
|
expected: param_tys.len() + skip_indices.len(),
|
|
found: args.len(),
|
|
});
|
|
}
|
|
|
|
// Quoting https://github.com/rust-lang/rust/blob/6ef275e6c3cb1384ec78128eceeb4963ff788dca/src/librustc_typeck/check/mod.rs#L3325 --
|
|
// We do this in a pretty awful way: first we type-check any arguments
|
|
// that are not closures, then we type-check the closures. This is so
|
|
// that we have more information about the types of arguments when we
|
|
// type-check the functions. This isn't really the right way to do this.
|
|
for &check_closures in &[false, true] {
|
|
let mut skip_indices = skip_indices.into_iter().copied().fuse().peekable();
|
|
let param_iter = param_tys.iter().cloned().chain(repeat(self.err_ty()));
|
|
let expected_iter = expected_inputs
|
|
.iter()
|
|
.cloned()
|
|
.chain(param_iter.clone().skip(expected_inputs.len()));
|
|
for (idx, ((&arg, param_ty), expected_ty)) in
|
|
args.iter().zip(param_iter).zip(expected_iter).enumerate()
|
|
{
|
|
let is_closure = matches!(&self.body[arg], Expr::Lambda { .. });
|
|
if is_closure != check_closures {
|
|
continue;
|
|
}
|
|
|
|
while skip_indices.peek().map_or(false, |i| *i < idx as u32) {
|
|
skip_indices.next();
|
|
}
|
|
if skip_indices.peek().copied() == Some(idx as u32) {
|
|
continue;
|
|
}
|
|
|
|
// the difference between param_ty and expected here is that
|
|
// expected is the parameter when the expected *return* type is
|
|
// taken into account. So in `let _: &[i32] = identity(&[1, 2])`
|
|
// the expected type is already `&[i32]`, whereas param_ty is
|
|
// still an unbound type variable. We don't always want to force
|
|
// the parameter to coerce to the expected type (for example in
|
|
// `coerce_unsize_expected_type_4`).
|
|
let param_ty = self.normalize_associated_types_in(param_ty);
|
|
let expected = Expectation::rvalue_hint(&mut self.table, expected_ty);
|
|
// infer with the expected type we have...
|
|
let ty = self.infer_expr_inner(arg, &expected);
|
|
|
|
// then coerce to either the expected type or just the formal parameter type
|
|
let coercion_target = if let Some(ty) = expected.only_has_type(&mut self.table) {
|
|
// if we are coercing to the expectation, unify with the
|
|
// formal parameter type to connect everything
|
|
self.unify(&ty, ¶m_ty);
|
|
ty
|
|
} else {
|
|
param_ty
|
|
};
|
|
if !coercion_target.is_unknown() {
|
|
if self.coerce(Some(arg), &ty, &coercion_target).is_err() {
|
|
self.result.type_mismatches.insert(
|
|
arg.into(),
|
|
TypeMismatch { expected: coercion_target, actual: ty.clone() },
|
|
);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
fn substs_for_method_call(
|
|
&mut self,
|
|
def_generics: Generics,
|
|
generic_args: Option<&GenericArgs>,
|
|
) -> Substitution {
|
|
let (parent_params, self_params, type_params, const_params, impl_trait_params) =
|
|
def_generics.provenance_split();
|
|
assert_eq!(self_params, 0); // method shouldn't have another Self param
|
|
let total_len = parent_params + type_params + const_params + impl_trait_params;
|
|
let mut substs = Vec::with_capacity(total_len);
|
|
// Parent arguments are unknown
|
|
for (id, param) in def_generics.iter_parent() {
|
|
match param {
|
|
TypeOrConstParamData::TypeParamData(_) => {
|
|
substs.push(GenericArgData::Ty(self.table.new_type_var()).intern(Interner));
|
|
}
|
|
TypeOrConstParamData::ConstParamData(_) => {
|
|
let ty = self.db.const_param_ty(ConstParamId::from_unchecked(id));
|
|
substs
|
|
.push(GenericArgData::Const(self.table.new_const_var(ty)).intern(Interner));
|
|
}
|
|
}
|
|
}
|
|
// handle provided arguments
|
|
if let Some(generic_args) = generic_args {
|
|
// if args are provided, it should be all of them, but we can't rely on that
|
|
for (arg, kind_id) in generic_args
|
|
.args
|
|
.iter()
|
|
.filter(|arg| !matches!(arg, GenericArg::Lifetime(_)))
|
|
.take(type_params + const_params)
|
|
.zip(def_generics.iter_id().skip(parent_params))
|
|
{
|
|
if let Some(g) = generic_arg_to_chalk(
|
|
self.db,
|
|
kind_id,
|
|
arg,
|
|
self,
|
|
|this, type_ref| this.make_ty(type_ref),
|
|
|this, c, ty| {
|
|
const_or_path_to_chalk(
|
|
this.db,
|
|
&this.resolver,
|
|
ty,
|
|
c,
|
|
ParamLoweringMode::Placeholder,
|
|
|| generics(this.db.upcast(), (&this.resolver).generic_def().unwrap()),
|
|
DebruijnIndex::INNERMOST,
|
|
)
|
|
},
|
|
) {
|
|
substs.push(g);
|
|
}
|
|
}
|
|
};
|
|
for (id, data) in def_generics.iter().skip(substs.len()) {
|
|
match data {
|
|
TypeOrConstParamData::TypeParamData(_) => {
|
|
substs.push(GenericArgData::Ty(self.table.new_type_var()).intern(Interner))
|
|
}
|
|
TypeOrConstParamData::ConstParamData(_) => {
|
|
substs.push(
|
|
GenericArgData::Const(self.table.new_const_var(
|
|
self.db.const_param_ty(ConstParamId::from_unchecked(id)),
|
|
))
|
|
.intern(Interner),
|
|
)
|
|
}
|
|
}
|
|
}
|
|
assert_eq!(substs.len(), total_len);
|
|
Substitution::from_iter(Interner, substs)
|
|
}
|
|
|
|
fn register_obligations_for_call(&mut self, callable_ty: &Ty) {
|
|
let callable_ty = self.resolve_ty_shallow(callable_ty);
|
|
if let TyKind::FnDef(fn_def, parameters) = callable_ty.kind(Interner) {
|
|
let def: CallableDefId = from_chalk(self.db, *fn_def);
|
|
let generic_predicates = self.db.generic_predicates(def.into());
|
|
for predicate in generic_predicates.iter() {
|
|
let (predicate, binders) = predicate
|
|
.clone()
|
|
.substitute(Interner, parameters)
|
|
.into_value_and_skipped_binders();
|
|
always!(binders.len(Interner) == 0); // quantified where clauses not yet handled
|
|
self.push_obligation(predicate.cast(Interner));
|
|
}
|
|
// add obligation for trait implementation, if this is a trait method
|
|
match def {
|
|
CallableDefId::FunctionId(f) => {
|
|
if let ItemContainerId::TraitId(trait_) = f.lookup(self.db.upcast()).container {
|
|
// construct a TraitRef
|
|
let substs = crate::subst_prefix(
|
|
&*parameters,
|
|
generics(self.db.upcast(), trait_.into()).len(),
|
|
);
|
|
self.push_obligation(
|
|
TraitRef { trait_id: to_chalk_trait_id(trait_), substitution: substs }
|
|
.cast(Interner),
|
|
);
|
|
}
|
|
}
|
|
CallableDefId::StructId(_) | CallableDefId::EnumVariantId(_) => {}
|
|
}
|
|
}
|
|
}
|
|
|
|
/// Returns the argument indices to skip.
|
|
fn check_legacy_const_generics(&mut self, callee: Ty, args: &[ExprId]) -> Vec<u32> {
|
|
let (func, subst) = match callee.kind(Interner) {
|
|
TyKind::FnDef(fn_id, subst) => {
|
|
let callable = CallableDefId::from_chalk(self.db, *fn_id);
|
|
let func = match callable {
|
|
CallableDefId::FunctionId(f) => f,
|
|
_ => return Vec::new(),
|
|
};
|
|
(func, subst)
|
|
}
|
|
_ => return Vec::new(),
|
|
};
|
|
|
|
let data = self.db.function_data(func);
|
|
if data.legacy_const_generics_indices.is_empty() {
|
|
return Vec::new();
|
|
}
|
|
|
|
// only use legacy const generics if the param count matches with them
|
|
if data.params.len() + data.legacy_const_generics_indices.len() != args.len() {
|
|
if args.len() <= data.params.len() {
|
|
return Vec::new();
|
|
} else {
|
|
// there are more parameters than there should be without legacy
|
|
// const params; use them
|
|
let mut indices = data.legacy_const_generics_indices.clone();
|
|
indices.sort();
|
|
return indices;
|
|
}
|
|
}
|
|
|
|
// check legacy const parameters
|
|
for (subst_idx, arg_idx) in data.legacy_const_generics_indices.iter().copied().enumerate() {
|
|
let arg = match subst.at(Interner, subst_idx).constant(Interner) {
|
|
Some(c) => c,
|
|
None => continue, // not a const parameter?
|
|
};
|
|
if arg_idx >= args.len() as u32 {
|
|
continue;
|
|
}
|
|
let _ty = arg.data(Interner).ty.clone();
|
|
let expected = Expectation::none(); // FIXME use actual const ty, when that is lowered correctly
|
|
self.infer_expr(args[arg_idx as usize], &expected);
|
|
// FIXME: evaluate and unify with the const
|
|
}
|
|
let mut indices = data.legacy_const_generics_indices.clone();
|
|
indices.sort();
|
|
indices
|
|
}
|
|
|
|
fn builtin_binary_op_return_ty(&mut self, op: BinaryOp, lhs_ty: Ty, rhs_ty: Ty) -> Option<Ty> {
|
|
let lhs_ty = self.resolve_ty_shallow(&lhs_ty);
|
|
let rhs_ty = self.resolve_ty_shallow(&rhs_ty);
|
|
match op {
|
|
BinaryOp::LogicOp(_) | BinaryOp::CmpOp(_) => {
|
|
Some(TyKind::Scalar(Scalar::Bool).intern(Interner))
|
|
}
|
|
BinaryOp::Assignment { .. } => Some(TyBuilder::unit()),
|
|
BinaryOp::ArithOp(ArithOp::Shl | ArithOp::Shr) => {
|
|
// all integer combinations are valid here
|
|
if matches!(
|
|
lhs_ty.kind(Interner),
|
|
TyKind::Scalar(Scalar::Int(_) | Scalar::Uint(_))
|
|
| TyKind::InferenceVar(_, TyVariableKind::Integer)
|
|
) && matches!(
|
|
rhs_ty.kind(Interner),
|
|
TyKind::Scalar(Scalar::Int(_) | Scalar::Uint(_))
|
|
| TyKind::InferenceVar(_, TyVariableKind::Integer)
|
|
) {
|
|
Some(lhs_ty)
|
|
} else {
|
|
None
|
|
}
|
|
}
|
|
BinaryOp::ArithOp(_) => match (lhs_ty.kind(Interner), rhs_ty.kind(Interner)) {
|
|
// (int, int) | (uint, uint) | (float, float)
|
|
(TyKind::Scalar(Scalar::Int(_)), TyKind::Scalar(Scalar::Int(_)))
|
|
| (TyKind::Scalar(Scalar::Uint(_)), TyKind::Scalar(Scalar::Uint(_)))
|
|
| (TyKind::Scalar(Scalar::Float(_)), TyKind::Scalar(Scalar::Float(_))) => {
|
|
Some(rhs_ty)
|
|
}
|
|
// ({int}, int) | ({int}, uint)
|
|
(
|
|
TyKind::InferenceVar(_, TyVariableKind::Integer),
|
|
TyKind::Scalar(Scalar::Int(_) | Scalar::Uint(_)),
|
|
) => Some(rhs_ty),
|
|
// (int, {int}) | (uint, {int})
|
|
(
|
|
TyKind::Scalar(Scalar::Int(_) | Scalar::Uint(_)),
|
|
TyKind::InferenceVar(_, TyVariableKind::Integer),
|
|
) => Some(lhs_ty),
|
|
// ({float} | float)
|
|
(
|
|
TyKind::InferenceVar(_, TyVariableKind::Float),
|
|
TyKind::Scalar(Scalar::Float(_)),
|
|
) => Some(rhs_ty),
|
|
// (float, {float})
|
|
(
|
|
TyKind::Scalar(Scalar::Float(_)),
|
|
TyKind::InferenceVar(_, TyVariableKind::Float),
|
|
) => Some(lhs_ty),
|
|
// ({int}, {int}) | ({float}, {float})
|
|
(
|
|
TyKind::InferenceVar(_, TyVariableKind::Integer),
|
|
TyKind::InferenceVar(_, TyVariableKind::Integer),
|
|
)
|
|
| (
|
|
TyKind::InferenceVar(_, TyVariableKind::Float),
|
|
TyKind::InferenceVar(_, TyVariableKind::Float),
|
|
) => Some(rhs_ty),
|
|
_ => None,
|
|
},
|
|
}
|
|
}
|
|
|
|
fn builtin_binary_op_rhs_expectation(&mut self, op: BinaryOp, lhs_ty: Ty) -> Option<Ty> {
|
|
Some(match op {
|
|
BinaryOp::LogicOp(..) => TyKind::Scalar(Scalar::Bool).intern(Interner),
|
|
BinaryOp::Assignment { op: None } => lhs_ty,
|
|
BinaryOp::CmpOp(CmpOp::Eq { .. }) => match self
|
|
.resolve_ty_shallow(&lhs_ty)
|
|
.kind(Interner)
|
|
{
|
|
TyKind::Scalar(_) | TyKind::Str => lhs_ty,
|
|
TyKind::InferenceVar(_, TyVariableKind::Integer | TyVariableKind::Float) => lhs_ty,
|
|
_ => return None,
|
|
},
|
|
BinaryOp::ArithOp(ArithOp::Shl | ArithOp::Shr) => return None,
|
|
BinaryOp::CmpOp(CmpOp::Ord { .. })
|
|
| BinaryOp::Assignment { op: Some(_) }
|
|
| BinaryOp::ArithOp(_) => match self.resolve_ty_shallow(&lhs_ty).kind(Interner) {
|
|
TyKind::Scalar(Scalar::Int(_) | Scalar::Uint(_) | Scalar::Float(_)) => lhs_ty,
|
|
TyKind::InferenceVar(_, TyVariableKind::Integer | TyVariableKind::Float) => lhs_ty,
|
|
_ => return None,
|
|
},
|
|
})
|
|
}
|
|
|
|
fn resolve_binop_method(&self, op: BinaryOp) -> Option<FunctionId> {
|
|
let (name, lang_item) = match op {
|
|
BinaryOp::LogicOp(_) => return None,
|
|
BinaryOp::ArithOp(aop) => match aop {
|
|
ArithOp::Add => (name!(add), name!(add)),
|
|
ArithOp::Mul => (name!(mul), name!(mul)),
|
|
ArithOp::Sub => (name!(sub), name!(sub)),
|
|
ArithOp::Div => (name!(div), name!(div)),
|
|
ArithOp::Rem => (name!(rem), name!(rem)),
|
|
ArithOp::Shl => (name!(shl), name!(shl)),
|
|
ArithOp::Shr => (name!(shr), name!(shr)),
|
|
ArithOp::BitXor => (name!(bitxor), name!(bitxor)),
|
|
ArithOp::BitOr => (name!(bitor), name!(bitor)),
|
|
ArithOp::BitAnd => (name!(bitand), name!(bitand)),
|
|
},
|
|
BinaryOp::Assignment { op: Some(aop) } => match aop {
|
|
ArithOp::Add => (name!(add_assign), name!(add_assign)),
|
|
ArithOp::Mul => (name!(mul_assign), name!(mul_assign)),
|
|
ArithOp::Sub => (name!(sub_assign), name!(sub_assign)),
|
|
ArithOp::Div => (name!(div_assign), name!(div_assign)),
|
|
ArithOp::Rem => (name!(rem_assign), name!(rem_assign)),
|
|
ArithOp::Shl => (name!(shl_assign), name!(shl_assign)),
|
|
ArithOp::Shr => (name!(shr_assign), name!(shr_assign)),
|
|
ArithOp::BitXor => (name!(bitxor_assign), name!(bitxor_assign)),
|
|
ArithOp::BitOr => (name!(bitor_assign), name!(bitor_assign)),
|
|
ArithOp::BitAnd => (name!(bitand_assign), name!(bitand_assign)),
|
|
},
|
|
BinaryOp::CmpOp(cop) => match cop {
|
|
CmpOp::Eq { negated: false } => (name!(eq), name!(eq)),
|
|
CmpOp::Eq { negated: true } => (name!(ne), name!(eq)),
|
|
CmpOp::Ord { ordering: Ordering::Less, strict: false } => {
|
|
(name!(le), name!(partial_ord))
|
|
}
|
|
CmpOp::Ord { ordering: Ordering::Less, strict: true } => {
|
|
(name!(lt), name!(partial_ord))
|
|
}
|
|
CmpOp::Ord { ordering: Ordering::Greater, strict: false } => {
|
|
(name!(ge), name!(partial_ord))
|
|
}
|
|
CmpOp::Ord { ordering: Ordering::Greater, strict: true } => {
|
|
(name!(gt), name!(partial_ord))
|
|
}
|
|
},
|
|
BinaryOp::Assignment { op: None } => return None,
|
|
};
|
|
|
|
let trait_ = self.resolve_lang_item(lang_item)?.as_trait()?;
|
|
|
|
self.db.trait_data(trait_).method_by_name(&name)
|
|
}
|
|
}
|