virtual keyword parsing and ast

crates/parser/src/ast/top_level.rs

@@ -107,12 +107,13 @@ pub struct Override(pub Option<ExprPath>);
 #[derive(Debug, Clone, Serialize)]
 pub struct FunctionDecl {
     pub visibility: Visibility,
-    pub is_override: Option<Override>,
+    pub is_virtual: bool,
+    pub return_type: Option<TypeExpr>,
     pub name: Identifier,
     pub generics: GenericsDecl,
     pub self_param: Option<(bool, Option<Identifier>, bool)>,
     pub params: ParamList,
-    pub return_type: Option<TypeExpr>,
+    pub is_override: Option<Override>,
     pub body: Option<Block>,
 }
 
@@ -129,7 +130,6 @@ pub struct FieldDecl {
     pub visibility: Visibility,
     pub type_: TypeExpr,
     pub name: Identifier,
-    // pub tuple_names: Vec<Identifier>,
 }
 
 #[derive(Debug, Clone, Serialize)]

crates/parser/src/grammar.pest

@@ -36,6 +36,7 @@ keyword = {
   | "override"
   | "const"
   | "type"
+  | "virtual"
 }
 
 identifier = @{
@@ -373,10 +374,12 @@ trait_decl = {
 // FUNCTIONS
 // ======================================================
 
+virtual_kw = { "virtual" }
+
 override_kw = { "override" ~ ("(" ~ expr_path ~ ")")? }
 
 function_decl = {
-    visibility? ~ ("void" | type_expr) ~ identifier ~ generics_decl? ~ "(" ~ method_args ~ ")" ~ override_kw? ~ (block | semicolon)
+    visibility? ~ virtual_kw? ~ ("void" | type_expr) ~ identifier ~ generics_decl? ~ "(" ~ method_args ~ ")" ~ override_kw? ~ (block | semicolon)
 }
 
 // ======================================================

crates/parser/src/parser/items/function.rs

@@ -14,6 +14,8 @@ impl<'a> TryFrom<pest::iterators::Pair<'a, Rule>> for FunctionDecl {
         let mut inner = pair.into_inner();
             let visibility = Visibility::try_from(&mut inner)?;
 
+            let is_virtual = listen_rule(&mut inner, Rule::virtual_kw);
+
             let return_type = consume_rule(&mut inner, Rule::type_expr)
                 .map(TypeExpr::try_from)
                 .transpose()?;
@@ -45,12 +47,13 @@ impl<'a> TryFrom<pest::iterators::Pair<'a, Rule>> for FunctionDecl {
 
             Ok(Self {
                 visibility: visibility,
-                is_override: is_override,
+                is_virtual: is_virtual,
                 return_type: return_type,
                 name: name,
                 generics: generics,
                 self_param: self_param,
                 params: params,
+                is_override: is_override,
                 body: body,
             })
         })