Add initial (flawed) implementation of binding annotations

crates/ra_syntax/src/ast.rs

@@ -713,6 +713,16 @@ impl FieldPatList {
     }
 }
 
+impl BindPat {
+    pub fn is_mutable(&self) -> bool {
+        self.syntax().children().any(|n| n.kind() == MUT_KW)
+    }
+
+    pub fn is_ref(&self) -> bool {
+        self.syntax().children().any(|n| n.kind() == REF_KW)
+    }
+}
+
 #[test]
 fn test_doc_comment_of_items() {
     let file = SourceFile::parse(

crates/ra_syntax/src/ast/generated.rs

@@ -180,7 +180,11 @@ impl AstNode for BindPat {
 
 
 impl ast::NameOwner for BindPat {}
-impl BindPat {}
+impl BindPat {
+    pub fn pat(&self) -> Option<&Pat> {
+        super::child_opt(self)
+    }
+}
 
 // Block
 #[derive(Debug, PartialEq, Eq, Hash)]

crates/ra_syntax/src/grammar.ron

@@ -488,7 +488,10 @@ Grammar(
         ),
 
         "RefPat": ( options: [ "Pat" ]),
-        "BindPat": ( traits: ["NameOwner"] ),
+        "BindPat": ( 
+            options: [ "Pat" ],
+            traits: ["NameOwner"]
+        ),
         "PlaceholderPat": (),
         "PathPat": ( options: [ "Path" ] ),
         "StructPat": ( options: ["FieldPatList", "Path"] ),