ast: Add the "Self" type in preparation for cl-typeck

libconlang/src/ast.rs

@@ -187,6 +187,7 @@ pub struct Ty {
 pub enum TyKind {
     Never,
     Empty,
+    SelfTy,
     Path(Path),
     Tuple(TyTuple),
     Ref(TyRef),

libconlang/src/ast/ast_impl.rs

@@ -214,6 +214,7 @@ mod display {
             match &self.kind {
                 TyKind::Never => "!".fmt(f),
                 TyKind::Empty => "()".fmt(f),
+                TyKind::SelfTy => "Self".fmt(f),
                 TyKind::Path(v) => v.fmt(f),
                 TyKind::Tuple(v) => v.fmt(f),
                 TyKind::Ref(v) => v.fmt(f),

libconlang/src/parser.rs

@@ -676,6 +676,10 @@ impl<'t> Parser<'t> {
                 self.consume_peeked();
                 TyKind::Never
             }
+            Type::Keyword(Keyword::SelfTy) => {
+                self.consume_peeked();
+                TyKind::SelfTy
+            }
             Type::Amp | Type::AmpAmp => self.tyref()?.into(),
             Type::LParen => self.tytuple()?.into(),
             Type::Keyword(Keyword::Fn) => self.tyfn()?.into(),