rustc: Implement typechecking for simple monomorphic derivable traits on monomorphic types. r=brson

7 files changed, 42 insertions, 22 deletions

diff --git a/src/libsyntax/ast.rs b/src/libsyntax/ast.rs
index a3d2fe96b5d..579699c9958 100644
--- a/src/libsyntax/ast.rs
+++ b/src/libsyntax/ast.rs
@@ -1508,7 +1508,7 @@ enum item_ {
     item_impl(~[ty_param],
               Option<@trait_ref>, /* (optional) trait this impl implements */
               @Ty, /* self */
-              ~[@method]),
+              Option<~[@method]>),
     item_mac(mac),
 }
 
diff --git a/src/libsyntax/ast_map.rs b/src/libsyntax/ast_map.rs
index 8555ceed2db..bcda838b248 100644
--- a/src/libsyntax/ast_map.rs
+++ b/src/libsyntax/ast_map.rs
@@ -202,11 +202,13 @@ fn map_item(i: @item, cx: ctx, v: vt) {
     let item_path = @/* FIXME (#2543) */ copy cx.path;
     cx.map.insert(i.id, node_item(i, item_path));
     match i.node {
-      item_impl(_, _, _, ms) => {
+      item_impl(_, _, _, ms_opt) => {
         let impl_did = ast_util::local_def(i.id);
-        for ms.each |m| {
-            map_method(impl_did, extend(cx, i.ident), *m,
-                       cx);
+        for ms_opt.each |ms| {
+            for ms.each |m| {
+                map_method(impl_did, extend(cx, i.ident), *m,
+                           cx);
+            }
         }
       }
       item_enum(enum_definition, _) => {
diff --git a/src/libsyntax/ext/auto_serialize.rs b/src/libsyntax/ext/auto_serialize.rs
index 47e61c26f38..707787e78b9 100644
--- a/src/libsyntax/ext/auto_serialize.rs
+++ b/src/libsyntax/ext/auto_serialize.rs
@@ -398,7 +398,7 @@ fn mk_impl(
         ident: ast::token::special_idents::clownshoes_extensions,
         attrs: ~[],
         id: cx.next_id(),
-        node: ast::item_impl(trait_tps, opt_trait, ty, ~[f(ty)]),
+        node: ast::item_impl(trait_tps, opt_trait, ty, Some(~[f(ty)])),
         vis: ast::public,
         span: span,
     }
diff --git a/src/libsyntax/fold.rs b/src/libsyntax/fold.rs
index 311928dd4e0..7eb7b2853e3 100644
--- a/src/libsyntax/fold.rs
+++ b/src/libsyntax/fold.rs
@@ -248,11 +248,13 @@ fn noop_fold_item_underscore(i: item_, fld: ast_fold) -> item_ {
             let struct_def = fold_struct_def(struct_def, fld);
               item_class(struct_def, /* FIXME (#2543) */ copy typms)
           }
-          item_impl(tps, ifce, ty, methods) => {
+          item_impl(tps, ifce, ty, ref methods_opt) => {
               item_impl(fold_ty_params(tps, fld),
                         ifce.map(|p| fold_trait_ref(*p, fld)),
                         fld.fold_ty(ty),
-                        vec::map(methods, |x| fld.fold_method(*x)))
+                        option::map(methods_opt,
+                                    |methods| vec::map(
+                                        *methods, |x| fld.fold_method(*x))))
           }
           item_trait(tps, traits, methods) => {
             item_trait(fold_ty_params(tps, fld),
diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs
index 925da063ca6..672f86b7a10 100644
--- a/src/libsyntax/parse/parser.rs
+++ b/src/libsyntax/parse/parser.rs
@@ -2603,13 +2603,20 @@ impl Parser {
             None
         };
 
-        let mut meths = ~[];
-        self.expect(token::LBRACE);
-        while !self.eat(token::RBRACE) {
-            let vis = self.parse_visibility();
-            meths.push(self.parse_method(vis));
+        let meths_opt;
+        if self.eat(token::SEMI) {
+            meths_opt = None;
+        } else {
+            let mut meths = ~[];
+            self.expect(token::LBRACE);
+            while !self.eat(token::RBRACE) {
+                let vis = self.parse_visibility();
+                meths.push(self.parse_method(vis));
+            }
+            meths_opt = Some(move meths);
         }
-        (ident, item_impl(tps, opt_trait, ty, meths), None)
+
+        (ident, item_impl(tps, opt_trait, ty, meths_opt), None)
     }
 
     // Instantiates ident <i> with references to <typarams> as arguments.
diff --git a/src/libsyntax/print/pprust.rs b/src/libsyntax/print/pprust.rs
index 33915c8c0c9..d68b28c6836 100644
--- a/src/libsyntax/print/pprust.rs
+++ b/src/libsyntax/print/pprust.rs
@@ -522,7 +522,7 @@ fn print_item(s: ps, &&item: @ast::item) {
           print_struct(s, struct_def, tps, item.ident, item.span);
       }
 
-      ast::item_impl(tps, opt_trait, ty, methods) => {
+      ast::item_impl(tps, opt_trait, ty, methods_opt) => {
         head(s, visibility_qualified(item.vis, ~"impl"));
         if tps.is_not_empty() {
             print_type_params(s, tps);
@@ -539,11 +539,18 @@ fn print_item(s: ps, &&item: @ast::item) {
         };
         space(s.s);
 
-        bopen(s);
-        for methods.each |meth| {
-           print_method(s, *meth);
+        match methods_opt {
+            None => {
+                word(s.s, ~";");
+            }
+            Some(methods) => {
+                bopen(s);
+                for methods.each |meth| {
+                   print_method(s, *meth);
+                }
+                bclose(s, item.span);
+            }
         }
-        bclose(s, item.span);
       }
       ast::item_trait(tps, traits, methods) => {
         head(s, visibility_qualified(item.vis, ~"trait"));
diff --git a/src/libsyntax/visit.rs b/src/libsyntax/visit.rs
index b45af2d4ae8..7035400f92d 100644
--- a/src/libsyntax/visit.rs
+++ b/src/libsyntax/visit.rs
@@ -142,14 +142,16 @@ fn visit_item<E>(i: @item, e: E, v: vt<E>) {
         v.visit_ty_params(tps, e, v);
         visit_enum_def(enum_definition, tps, e, v);
       }
-      item_impl(tps, traits, ty, methods) => {
+      item_impl(tps, traits, ty, methods_opt) => {
         v.visit_ty_params(tps, e, v);
         for traits.each |p| {
             visit_path(p.path, e, v);
         }
         v.visit_ty(ty, e, v);
-        for methods.each |m| {
-            visit_method_helper(*m, e, v)
+        for methods_opt.each |methods| {
+            for methods.each |m| {
+                visit_method_helper(*m, e, v)
+            }
         }
       }
       item_class(struct_def, tps) => {