Implement typechecking for monomorphic "deriving" traits

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),
 }
 

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, _) => {

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,
     }

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),

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.

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"));

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) => {

src/rustc/metadata/encoder.rs

@@ -712,7 +712,7 @@ fn encode_info_for_item(ecx: @encode_ctxt, ebml_w: ebml::Serializer,
         encode_index(ebml_w, bkts, write_int);
         ebml_w.end_tag();
       }
-      item_impl(tps, opt_trait, ty, methods) => {
+      item_impl(tps, opt_trait, ty, methods_opt) => {
         add_to_index();
         ebml_w.start_tag(tag_items_data_item);
         encode_def_id(ebml_w, local_def(item.id));
@@ -729,10 +729,13 @@ fn encode_info_for_item(ecx: @encode_ctxt, ebml_w: ebml::Serializer,
             }
             _ => {}
         }
-        for methods.each |m| {
-            ebml_w.start_tag(tag_item_impl_method);
-            ebml_w.writer.write(str::to_bytes(def_to_str(local_def(m.id))));
-            ebml_w.end_tag();
+        for methods_opt.each |methods| {
+            for methods.each |m| {
+                ebml_w.start_tag(tag_item_impl_method);
+                let method_def_id = local_def(m.id);
+                ebml_w.writer.write(str::to_bytes(def_to_str(method_def_id)));
+                ebml_w.end_tag();
+            }
         }
         do opt_trait.iter() |associated_trait| {
            encode_trait_ref(ebml_w, ecx, *associated_trait)
@@ -742,11 +745,13 @@ fn encode_info_for_item(ecx: @encode_ctxt, ebml_w: ebml::Serializer,
 
         let impl_path = vec::append_one(path,
                                         ast_map::path_name(item.ident));
-        for methods.each |m| {
-            index.push({val: m.id, pos: ebml_w.writer.tell()});
-            encode_info_for_method(ecx, ebml_w, impl_path,
-                                   should_inline(m.attrs), item.id, *m,
-                                   vec::append(tps, m.tps));
+        for methods_opt.each |methods| {
+            for methods.each |m| {
+                index.push({val: m.id, pos: ebml_w.writer.tell()});
+                encode_info_for_method(ecx, ebml_w, impl_path,
+                                       should_inline(m.attrs), item.id, *m,
+                                       vec::append(tps, m.tps));
+            }
         }
       }
       item_trait(tps, traits, ms) => {

src/rustc/middle/resolve.rs

@@ -1192,7 +1192,7 @@ impl Resolver {
                 visit_item(item, new_parent, visitor);
             }
 
-            item_impl(_, trait_ref_opt, ty, methods) => {
+            item_impl(_, trait_ref_opt, ty, methods_opt) => {
                 // If this implements an anonymous trait and it has static
                 // methods, then add all the static methods within to a new
                 // module, if the type was defined within this module.
@@ -1203,10 +1203,12 @@ impl Resolver {
 
                 // Bail out early if there are no static methods.
                 let mut has_static_methods = false;
-                for methods.each |method| {
-                    match method.self_ty.node {
-                        sty_static => has_static_methods = true,
-                        _ => {}
+                for methods_opt.each |methods| {
+                    for methods.each |method| {
+                        match method.self_ty.node {
+                            sty_static => has_static_methods = true,
+                            _ => {}
+                        }
                     }
                 }
 
@@ -1233,22 +1235,26 @@ impl Resolver {
                             name_bindings.get_module());
 
                         // For each static method...
-                        for methods.each |method| {
-                            match method.self_ty.node {
-                                sty_static => {
-                                    // Add the static method to the module.
-                                    let ident = method.ident;
-                                    let (method_name_bindings, _) =
-                                        self.add_child(ident,
-                                                       new_parent,
-                                                       ForbidDuplicateValues,
-                                                       method.span);
-                                    let def = def_fn(local_def(method.id),
-                                                     method.purity);
-                                    method_name_bindings.define_value(
-                                        Public, def, method.span);
+                        for methods_opt.each |methods| {
+                            for methods.each |method| {
+                                match method.self_ty.node {
+                                    sty_static => {
+                                        // Add the static method to the
+                                        // module.
+                                        let ident = method.ident;
+                                        let (method_name_bindings, _) =
+                                            self.add_child(
+                                                ident,
+                                                new_parent,
+                                                ForbidDuplicateValues,
+                                                method.span);
+                                        let def = def_fn(local_def(method.id),
+                                                         method.purity);
+                                        method_name_bindings.define_value(
+                                            Public, def, method.span);
+                                    }
+                                    _ => {}
                                 }
-                                _ => {}
                             }
                         }
                     }
@@ -3446,12 +3452,14 @@ impl Resolver {
             }
 
             item_impl(type_parameters, implemented_traits, self_type,
-                      methods) => {
-
-                self.resolve_implementation(item.id, item.span,
+                      methods_opt) => {
+                self.resolve_implementation(item.id,
+                                            item.span,
                                             type_parameters,
                                             implemented_traits,
-                                            self_type, methods, visitor);
+                                            self_type,
+                                            methods_opt,
+                                            visitor);
             }
 
             item_trait(type_parameters, traits, methods) => {
@@ -3876,7 +3884,7 @@ impl Resolver {
                               type_parameters: ~[ty_param],
                               opt_trait_reference: Option<@trait_ref>,
                               self_type: @Ty,
-                              methods: ~[@method],
+                              opt_methods: Option<~[@method]>,
                               visitor: ResolveVisitor) {
         // If applicable, create a rib for the type parameters.
         let outer_type_parameter_count = type_parameters.len();
@@ -3915,27 +3923,33 @@ impl Resolver {
             // Resolve the self type.
             self.resolve_type(self_type, visitor);
 
-            for methods.each |method| {
-                // We also need a new scope for the method-specific
-                // type parameters.
-                self.resolve_method(MethodRibKind(id, Provided(method.id)),
-                                    *method,
-                                    outer_type_parameter_count,
-                                    visitor);
+            for opt_methods.each |methods| {
+                for methods.each |method| {
+                    // We also need a new scope for the method-specific
+                    // type parameters.
+                    self.resolve_method(MethodRibKind(
+                        id,
+                        Provided(method.id)),
+                        *method,
+                        outer_type_parameter_count,
+                        visitor);
 /*
-                let borrowed_type_parameters = &method.tps;
-                self.resolve_function(MethodRibKind(id, Provided(method.id)),
-                                      Some(@method.decl),
-                                      HasTypeParameters
-                                        (borrowed_type_parameters,
-                                         method.id,
-                                         outer_type_parameter_count,
-                                         NormalRibKind),
-                                      method.body,
-                                      HasSelfBinding(method.self_id),
-                                      NoCaptureClause,
-                                      visitor);
+                    let borrowed_type_parameters = &method.tps;
+                    self.resolve_function(MethodRibKind(
+                                          id,
+                                          Provided(method.id)),
+                                          Some(@method.decl),
+                                          HasTypeParameters
+                                            (borrowed_type_parameters,
+                                             method.id,
+                                             outer_type_parameter_count,
+                                             NormalRibKind),
+                                          method.body,
+                                          HasSelfBinding(method.self_id),
+                                          NoCaptureClause,
+                                          visitor);
 */
+                }
             }
 
             // Restore the original trait references.

src/rustc/middle/trans/base.rs

@@ -1798,8 +1798,17 @@ fn trans_item(ccx: @crate_ctxt, item: ast::item) {
             }
         }
       }
-      ast::item_impl(tps, _, _, ms) => {
-        meth::trans_impl(ccx, *path, item.ident, ms, tps, None, item.id);
+      ast::item_impl(tps, _, _, ms_opt) => {
+        match ms_opt {
+            None => {
+                deriving::trans_deriving_impl(ccx, *path, item.ident, tps,
+                                              None, item.id);
+            }
+            Some(ms) => {
+                meth::trans_impl(ccx, *path, item.ident, ms, tps, None,
+                                 item.id);
+            }
+        }
       }
       ast::item_mod(m) => {
         trans_mod(ccx, m);

src/rustc/middle/trans/deriving.rs

@@ -0,0 +1,21 @@
+// Translation of automatically-derived trait implementations. This handles
+// enums and structs only; other types cannot be automatically derived.
+
+use middle::trans::base::get_insn_ctxt;
+use middle::trans::common::crate_ctxt;
+use syntax::ast::{ident, node_id, ty_param};
+use syntax::ast_map::path;
+
+/// The main "translation" pass for automatically-derived impls. Generates
+/// code for monomorphic methods only. Other methods will be generated when
+/// they are invoked with specific type parameters; see
+/// `trans::base::lval_static_fn()` or `trans::base::monomorphic_fn()`.
+pub fn trans_deriving_impl(ccx: @crate_ctxt, _path: path, _name: ident,
+                           tps: ~[ty_param], _self_ty: Option<ty::t>,
+                           _id: node_id) {
+    let _icx = ccx.insn_ctxt("deriving::trans_deriving_impl");
+    if tps.len() > 0 { return; }
+
+    // XXX: Unimplemented.
+}
+

src/rustc/middle/trans/meth.rs

@@ -306,7 +306,8 @@ fn method_with_name(ccx: @crate_ctxt, impl_id: ast::def_id,
                     name: ast::ident) -> ast::def_id {
     if impl_id.crate == ast::local_crate {
         match ccx.tcx.items.get(impl_id.node) {
-          ast_map::node_item(@{node: ast::item_impl(_, _, _, ms), _}, _) => {
+          ast_map::node_item(@{node: ast::item_impl(_, _, _, Some(ms)), _},
+                             _) => {
             method_from_methods(ms, name)
           }
           ast_map::node_item(@{node:

src/rustc/middle/trans/reachable.rs

@@ -90,12 +90,14 @@ fn traverse_public_item(cx: ctx, item: @item) {
             traverse_inline_body(cx, blk);
         }
       }
-      item_impl(tps, _, _, ms) => {
-        for vec::each(ms) |m| {
-            if tps.len() > 0u || m.tps.len() > 0u ||
-               attr::find_inline_attr(m.attrs) != attr::ia_none {
-                cx.rmap.insert(m.id, ());
-                traverse_inline_body(cx, m.body);
+      item_impl(tps, _, _, ms_opt) => {
+        for ms_opt.each |ms| {
+            for vec::each(*ms) |m| {
+                if tps.len() > 0u || m.tps.len() > 0u ||
+                   attr::find_inline_attr(m.attrs) != attr::ia_none {
+                    cx.rmap.insert(m.id, ());
+                    traverse_inline_body(cx, m.body);
+                }
             }
         }
       }