ast: make `= <expr>;` optional in free statics/consts.

3 files changed, 5 insertions, 9 deletions

diff --git a/src/libsyntax/ast.rs b/src/libsyntax/ast.rs
index fe353bc994a..61ae14cae02 100644
--- a/src/libsyntax/ast.rs
+++ b/src/libsyntax/ast.rs
@@ -2496,11 +2496,11 @@ pub enum ItemKind {
     /// A static item (`static`).
     ///
     /// E.g., `static FOO: i32 = 42;` or `static FOO: &'static str = "bar";`.
-    Static(P<Ty>, Mutability, P<Expr>),
+    Static(P<Ty>, Mutability, Option<P<Expr>>),
     /// A constant item (`const`).
     ///
     /// E.g., `const FOO: i32 = 42;`.
-    Const(P<Ty>, P<Expr>),
+    Const(P<Ty>, Option<P<Expr>>),
     /// A function declaration (`fn`).
     ///
     /// E.g., `fn foo(bar: usize) -> usize { .. }`.
diff --git a/src/libsyntax/mut_visit.rs b/src/libsyntax/mut_visit.rs
index d36b0a28a8c..cd7a3becca7 100644
--- a/src/libsyntax/mut_visit.rs
+++ b/src/libsyntax/mut_visit.rs
@@ -890,13 +890,9 @@ pub fn noop_visit_item_kind<T: MutVisitor>(kind: &mut ItemKind, vis: &mut T) {
     match kind {
         ItemKind::ExternCrate(_orig_name) => {}
         ItemKind::Use(use_tree) => vis.visit_use_tree(use_tree),
-        ItemKind::Static(ty, _mut, expr) => {
+        ItemKind::Static(ty, _, expr) | ItemKind::Const(ty, expr) => {
             vis.visit_ty(ty);
-            vis.visit_expr(expr);
-        }
-        ItemKind::Const(ty, expr) => {
-            vis.visit_ty(ty);
-            vis.visit_expr(expr);
+            visit_opt(expr, |expr| vis.visit_expr(expr));
         }
         ItemKind::Fn(sig, generics, body) => {
             visit_fn_sig(sig, vis);
diff --git a/src/libsyntax/visit.rs b/src/libsyntax/visit.rs
index ed57fc8abf3..4beb94e9f0c 100644
--- a/src/libsyntax/visit.rs
+++ b/src/libsyntax/visit.rs
@@ -300,7 +300,7 @@ pub fn walk_item<'a, V: Visitor<'a>>(visitor: &mut V, item: &'a Item) {
         ItemKind::Use(ref use_tree) => visitor.visit_use_tree(use_tree, item.id, false),
         ItemKind::Static(ref typ, _, ref expr) | ItemKind::Const(ref typ, ref expr) => {
             visitor.visit_ty(typ);
-            visitor.visit_expr(expr);
+            walk_list!(visitor, visit_expr, expr);
         }
         ItemKind::Fn(ref sig, ref generics, ref body) => {
             visitor.visit_generics(generics);