bjoernager/rust
bjoernager/rust
1
Fork 0
Code Issues Pull requests Activity

Add generic arg infer

Browse source
This commit is contained in:
kadmin 2021-04-24 21:41:57 +00:00
parent 71a6c7c803
commit 417b098cfc
28 changed files with 265 additions and 89 deletions
Download patch file Download diff file Expand all files Collapse all files

77
compiler/rustc_ast_lowering/src/lib.rs
View file

@ -1218,48 +1218,55 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
match arg {
ast::GenericArg::Lifetime(lt) => GenericArg::Lifetime(self.lower_lifetime(&lt)),
ast::GenericArg::Type(ty) => {
// We parse const arguments as path types as we cannot distinguish them during
// parsing. We try to resolve that ambiguity by attempting resolution in both the
// type and value namespaces. If we resolved the path in the value namespace, we
// transform it into a generic const argument.
if let TyKind::Path(ref qself, ref path) = ty.kind {
if let Some(partial_res) = self.resolver.get_partial_res(ty.id) {
let res = partial_res.base_res();
if !res.matches_ns(Namespace::TypeNS) {
debug!(
"lower_generic_arg: Lowering type argument as const argument: {:?}",
ty,
);
match ty.kind {
TyKind::Infer => {
let hir_id = self.lower_node_id(ty.id);
return GenericArg::Infer(hir::InferArg { hir_id, span: ty.span });
}
// We parse const arguments as path types as we cannot distinguish them during
// parsing. We try to resolve that ambiguity by attempting resolution in both the
// type and value namespaces. If we resolved the path in the value namespace, we
// transform it into a generic const argument.
TyKind::Path(ref qself, ref path) => {
if let Some(partial_res) = self.resolver.get_partial_res(ty.id) {
let res = partial_res.base_res();
if !res.matches_ns(Namespace::TypeNS) {
debug!(
"lower_generic_arg: Lowering type argument as const argument: {:?}",
ty,
);
// Construct a AnonConst where the expr is the "ty"'s path.
// Construct a AnonConst where the expr is the "ty"'s path.
let parent_def_id = self.current_hir_id_owner.0;
let node_id = self.resolver.next_node_id();
let parent_def_id = self.current_hir_id_owner.0;
let node_id = self.resolver.next_node_id();
// Add a definition for the in-band const def.
self.resolver.create_def(
parent_def_id,
node_id,
DefPathData::AnonConst,
ExpnId::root(),
ty.span,
);
// Add a definition for the in-band const def.
self.resolver.create_def(
parent_def_id,
node_id,
DefPathData::AnonConst,
ExpnId::root(),
ty.span,
);
let path_expr = Expr {
id: ty.id,
kind: ExprKind::Path(qself.clone(), path.clone()),
span: ty.span,
attrs: AttrVec::new(),
tokens: None,
};
let path_expr = Expr {
id: ty.id,
kind: ExprKind::Path(qself.clone(), path.clone()),
span: ty.span,
attrs: AttrVec::new(),
tokens: None,
};
let ct = self.with_new_scopes(|this| hir::AnonConst {
hir_id: this.lower_node_id(node_id),
body: this.lower_const_body(path_expr.span, Some(&path_expr)),
});
return GenericArg::Const(ConstArg { value: ct, span: ty.span });
let ct = self.with_new_scopes(|this| hir::AnonConst {
hir_id: this.lower_node_id(node_id),
body: this.lower_const_body(path_expr.span, Some(&path_expr)),
});
return GenericArg::Const(ConstArg { value: ct, span: ty.span });
}
}
}
_ => {}
}
GenericArg::Type(self.lower_ty_direct(&ty, itctx))
}