1 files changed, 43 insertions, 14 deletions

diff --git a/src/ast/attrs.hpp b/src/ast/attrs.hpp
index ebbad066..b7b7f91c 100644
--- a/src/ast/attrs.hpp
+++ b/src/ast/attrs.hpp
@@ -14,13 +14,18 @@ public:
     ::std::vector<MetaItem> m_items;
     
     MetaItems() {}
+    MetaItems(MetaItems&&) = default;
+    MetaItems& operator=(MetaItems&&) = default;
+    MetaItems(const MetaItems&) = delete;
     MetaItems(::std::vector<MetaItem> items):
-        m_items(items)
+        m_items( mv$(items) )
     {
     }
     
     void push_back(MetaItem i);
     
+    MetaItems clone() const;
+    
     MetaItem* get(const char *name);
     bool has(const char *name) {
         return get(name) != 0;
@@ -33,42 +38,66 @@ public:
     SERIALISABLE_PROTOTYPES();
 };
 
+
+TAGGED_UNION(MetaItemData, None,
+    (None, ()),
+    (String, (
+        ::std::string   val;
+        )),
+    (List, (
+        ::std::vector<MetaItem> sub_items;
+        ))
+    );
+
 class MetaItem:
     public Serialisable
 {
     ::std::string   m_name;
-    MetaItems   m_sub_items;
-    ::std::string   m_str_val;
+    MetaItemData    m_data;
 public:
     MetaItem() {}
     MetaItem(::std::string name):
-        m_name(name)
+        m_name(name),
+        m_data( MetaItemData::make_None({}) )
     {
     }
     MetaItem(::std::string name, ::std::string str_val):
         m_name(name),
-        m_str_val(str_val)
+        m_data( MetaItemData::make_String({mv$(str_val)}) )
     {
     }
     MetaItem(::std::string name, ::std::vector<MetaItem> items):
         m_name(name),
-        m_sub_items(items)
+        m_data( MetaItemData::make_List({mv$(items)}) )
     {
     }
     
+    MetaItem clone() const;
+    
     void mark_used() {}
     const ::std::string& name() const { return m_name; }
-    const ::std::string& string() const { return m_str_val; }
-    bool has_sub_items() const { return m_sub_items.m_items.size() > 0; }
-    const MetaItems& items() const { return m_sub_items; }
-    MetaItems& items() { return m_sub_items; }
+    
+    bool has_noarg() const { return m_data.is_None(); }
+    
+    bool has_string() const { return m_data.is_String(); }
+    const ::std::string& string() const { return m_data.as_String().val; }
+    
+    bool has_sub_items() const { return m_data.is_List(); }
+    const ::std::vector<MetaItem>& items() const { return m_data.as_List().sub_items; }
+    //::std::vector<MetaItem>& items() { return m_data.as_List().sub_items; }
     
     friend ::std::ostream& operator<<(::std::ostream& os, const MetaItem& x) {
         os << x.m_name;
-        if(x.m_sub_items.m_items.size())
-            os << "(" << x.m_sub_items.m_items << ")";
-        else
-            os << "=\"" << x.m_str_val << "\"";
+        TU_MATCH(MetaItemData, (x.m_data), (e),
+        (None,
+            ),
+        (String,
+            os << "=\"" << e.val << "\"";
+            ),
+        (List,
+            os << "(" << e.sub_items << ")";
+            )
+        )
         return os;
     }