Generate buffer type for bounded protocols

Author: eholk

src/libsyntax/ext/pipes/ast_builder.rs

@@ -91,9 +91,22 @@ trait ext_ctxt_ast_builder {
                     +params: ~[ast::ty_param]) -> @ast::item;
     fn item_ty(name: ident, ty: @ast::ty) -> @ast::item;
     fn ty_vars(+ty_params: ~[ast::ty_param]) -> ~[@ast::ty];
+    fn ty_field_imm(name: ident, ty: @ast::ty) -> ast::ty_field;
+    fn ty_rec(+~[ast::ty_field]) -> @ast::ty;
 }
 
 impl ast_builder of ext_ctxt_ast_builder for ext_ctxt {
+    fn ty_field_imm(name: ident, ty: @ast::ty) -> ast::ty_field {
+        {node: {ident: name, mt: { ty: ty, mutbl: ast::m_imm } },
+          span: empty_span()}
+    }
+
+    fn ty_rec(+fields: ~[ast::ty_field]) -> @ast::ty {
+        @{id: self.next_id(),
+          node: ast::ty_rec(fields),
+          span: empty_span()}
+    }
+
     fn ty_param(id: ast::ident, +bounds: ~[ast::ty_param_bound])
         -> ast::ty_param
     {

src/libsyntax/ext/pipes/pipec.rs

@@ -204,6 +204,7 @@ impl compile of to_type_decls for state {
 
 impl compile of gen_init for protocol {
     fn gen_init(cx: ext_ctxt) -> @ast::item {
+        #debug("gen_init");
         let start_state = self.states[0];
 
         let body = alt start_state.dir {
@@ -237,6 +238,23 @@ impl compile of gen_init for protocol {
             server_states += s.to_endpoint_decls(cx, recv);
         }
 
+        if self.is_bounded() {
+            vec::push(
+                items,
+                cx.item_ty(
+                    @~"buffer",
+                    cx.ty_rec(
+                        (copy self.states).map_to_vec(
+                            |s| cx.ty_field_imm(
+                                s.name,
+                                cx.ty_path_ast_builder(
+                                    (path(@~"pipes")
+                                     + @~"packet")
+                                    .add_ty(
+                                        cx.ty_path_ast_builder(
+                                            path(s.name)))))))))
+        }
+
         vec::push(items,
                   cx.item_mod(@~"client",
                               client_states));