Switch metadata::encoder to <V:Visitor> trait.

placate make tidy.  Remove dead code.

src/librustc/metadata/encoder.rs

@@ -39,7 +39,8 @@ use syntax::attr;
 use syntax::attr::AttrMetaMethods;
 use syntax::diagnostic::span_handler;
 use syntax::parse::token::special_idents;
-use syntax::{ast_util, oldvisit};
+use syntax::ast_util;
+use syntax::visit;
 use syntax::parse::token;
 use syntax;
 use writer = extra::ebml::writer;
@@ -1184,31 +1185,10 @@ fn encode_info_for_foreign_item(ecx: &EncodeContext,
     ebml_w.end_tag();
 }
 
-fn encode_info_for_items(ecx: &EncodeContext,
+fn my_visit_expr(_e:@expr) { }
-                         ebml_w: &mut writer::Encoder,
-                         crate: &Crate)
-                         -> ~[entry<i64>] {
-    let index = @mut ~[];
-    ebml_w.start_tag(tag_items_data);
-    index.push(entry { val: CRATE_NODE_ID as i64, pos: ebml_w.writer.tell() });
-    encode_info_for_mod(ecx,
-                        ebml_w,
-                        &crate.module,
-                        CRATE_NODE_ID,
-                        [],
-                        syntax::parse::token::special_idents::invalid,
-                        public);
-    let items = ecx.tcx.items;
 
-    // See comment in `encode_side_tables_for_ii` in astencode
+fn my_visit_item(i:@item, items: ast_map::map, ebml_w:&writer::Encoder,
-    let ecx_ptr : *() = unsafe { cast::transmute(ecx) };
+                 ecx_ptr:*int, index: @mut ~[entry<i64>]) {
-
-    oldvisit::visit_crate(crate, ((), oldvisit::mk_vt(@oldvisit::Visitor {
-        visit_expr: |_e, (_cx, _v)| { },
-        visit_item: {
-            let ebml_w = (*ebml_w).clone();
-            |i, (cx, v)| {
-                oldvisit::visit_item(i, (cx, v));
     match items.get_copy(&i.id) {
         ast_map::node_item(_, pt) => {
             let mut ebml_w = ebml_w.clone();
@@ -1218,12 +1198,10 @@ fn encode_info_for_items(ecx: &EncodeContext,
         }
         _ => fail!("bad item")
     }
-            }
+}
-        },
+
-        visit_foreign_item: {
+fn my_visit_foreign_item(ni:@foreign_item, items: ast_map::map, ebml_w:&writer::Encoder,
-            let ebml_w = (*ebml_w).clone();
+                         ecx_ptr:*int, index: @mut ~[entry<i64>]) {
-            |ni, (cx, v)| {
-                oldvisit::visit_foreign_item(ni, (cx, v));
     match items.get_copy(&ni.id) {
         ast_map::node_foreign_item(_, abi, _, pt) => {
             debug!("writing foreign item %s::%s",
@@ -1245,10 +1223,64 @@ fn encode_info_for_items(ecx: &EncodeContext,
         // case for separate item and foreign-item tables
         _ => fail!("bad foreign item")
     }
+}
+
+struct EncodeVisitor {
+    ebml_w_for_visit_item: writer::Encoder,
+    ebml_w_for_visit_foreign_item: writer::Encoder,
+    ecx_ptr:*int,
+    items: ast_map::map,
+    index: @mut ~[entry<i64>],
+}
+
+impl visit::Visitor<()> for EncodeVisitor {
+    fn visit_expr(&mut self, ex:@expr, _:()) { my_visit_expr(ex); }
+    fn visit_item(&mut self, i:@item, _:()) {
+        visit::walk_item(self, i, ());
+        my_visit_item(i,
+                      self.items,
+                      &self.ebml_w_for_visit_item,
+                      self.ecx_ptr,
+                      self.index);
     }
-        },
+    fn visit_foreign_item(&mut self, ni:@foreign_item, _:()) {
-        ..*oldvisit::default_visitor()
+        visit::walk_foreign_item(self, ni, ());
-    })));
+        my_visit_foreign_item(ni,
+                              self.items,
+                              &self.ebml_w_for_visit_foreign_item,
+                              self.ecx_ptr,
+                              self.index);
+    }
+}
+
+fn encode_info_for_items(ecx: &EncodeContext,
+                         ebml_w: &mut writer::Encoder,
+                         crate: &Crate)
+                         -> ~[entry<i64>] {
+    let index = @mut ~[];
+    ebml_w.start_tag(tag_items_data);
+    index.push(entry { val: CRATE_NODE_ID as i64, pos: ebml_w.writer.tell() });
+    encode_info_for_mod(ecx,
+                        ebml_w,
+                        &crate.module,
+                        CRATE_NODE_ID,
+                        [],
+                        syntax::parse::token::special_idents::invalid,
+                        public);
+    let items = ecx.tcx.items;
+
+    // See comment in `encode_side_tables_for_ii` in astencode
+    let ecx_ptr : *int = unsafe { cast::transmute(ecx) };
+    let mut visitor = EncodeVisitor {
+        index: index,
+        items: items,
+        ecx_ptr: ecx_ptr,
+        ebml_w_for_visit_item: (*ebml_w).clone(),
+        ebml_w_for_visit_foreign_item: (*ebml_w).clone(),
+    };
+
+    visit::walk_crate(&mut visitor, crate, ());
+
     ebml_w.end_tag();
     return /*bad*/(*index).clone();
 }