rework enums and unions and their relationship to each other

 * @enumTagName renamed to @tagName and it works on enums and
   union-enums
 * Remove the EnumTag type. Now there is only enum and union,
   and the tag type of a union is always an enum.
 * unions support specifying the tag enum type, and they support
   inferring an enum tag type.
 * Enums no longer support field types but they do support
   setting the tag values. Likewise union-enums when inferring
   an enum tag type support setting the tag values.
 * It is now an error for enums and unions to have 0 fields.
 * switch statements support union-enums

closes #618

1 files changed, 7 insertions, 0 deletions

diff --git a/src/ast_render.cpp b/src/ast_render.cpp
index cdc18c7252..4f4dc1decd 100644
--- a/src/ast_render.cpp
+++ b/src/ast_render.cpp
@@ -661,11 +661,18 @@ static void render_node_extra(AstRender *ar, AstNode *node, bool grouped) {
                 const char *layout_str = layout_string(node->data.container_decl.layout);
                 const char *container_str = container_string(node->data.container_decl.kind);
                 fprintf(ar->f, "%s%s", layout_str, container_str);
+                if (node->data.container_decl.auto_enum) {
+                    fprintf(ar->f, "(enum");
+                }
                 if (node->data.container_decl.init_arg_expr != nullptr) {
                     fprintf(ar->f, "(");
                     render_node_grouped(ar, node->data.container_decl.init_arg_expr);
                     fprintf(ar->f, ")");
                 }
+                if (node->data.container_decl.auto_enum) {
+                    fprintf(ar->f, ")");
+                }
+
                 fprintf(ar->f, " {\n");
                 ar->indent += ar->indent_size;
                 for (size_t field_i = 0; field_i < node->data.container_decl.fields.length; field_i += 1) {