Simplify trait gramamr

Author: matklad

crates/ra_syntax/src/ast/generated/nodes.rs

@@ -267,7 +267,6 @@ impl Impl {
     pub fn unsafe_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![unsafe]) }
     pub fn impl_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![impl]) }
     pub fn const_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![const]) }
-    pub fn ty(&self) -> Option<Type> { support::child(&self.syntax) }
     pub fn excl_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![!]) }
     pub fn for_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![for]) }
     pub fn assoc_item_list(&self) -> Option<AssocItemList> { support::child(&self.syntax) }

xtask/src/codegen/gen_syntax.rs

@@ -591,6 +591,8 @@ fn lower_rule(acc: &mut Vec<Field>, grammar: &Grammar, label: Option<&String>, r
                     | "index"
                     | "base"
                     | "value"
+                    | "target_type"
+                    | "target_trait"
             );
             if manually_implemented {
                 return;

xtask/src/codegen/rust.ungram

@@ -194,12 +194,11 @@ AssocItem =
 | TypeAlias
 
 Impl =
- Attr* Visibility?
- 'default'? 'unsafe'? 'impl' 'const'? GenericParamList? (
-   Type
- | '!'? Type 'for' Type
- ) WhereClause?
- AssocItemList
+  Attr* Visibility?
+  'default'? 'unsafe'? 'impl' 'const'? GenericParamList?
+  ('!'? target_trait:Type 'for')? target_type:Type
+  WhereClause?
+  AssocItemList
 
 ExternBlock =
   Attr* Abi ExternItemList