Add rather inefficient type_identity wrapping for std::set.

Accessing an element is O(N), as if it was walking a list.

library/LuaTypes.cpp

@@ -285,6 +285,9 @@ void container_identity::lua_item_read(lua_State *state, int fname_idx, void *pt
 
 void container_identity::lua_item_write(lua_State *state, int fname_idx, void *ptr, int idx, int val_index)
 {
+    if (is_readonly())
+        field_error(state, fname_idx, "container is read-only", "write");
+
     auto id = (type_identity*)lua_touserdata(state, UPVAL_ITEM_ID);
     void *pitem = item_pointer(id, ptr, idx);
     id->lua_write(state, fname_idx, pitem, val_index);

library/include/DataDefs.h

@@ -28,6 +28,7 @@ distribution.
 #include <sstream>
 #include <vector>
 #include <map>
+#include <set>
 
 #include "Core.h"
 #include "BitArray.h"

library/include/DataIdentity.h

@@ -115,6 +115,8 @@ namespace DFHack
         virtual void lua_item_read(lua_State *state, int fname_idx, void *ptr, int idx);
         virtual void lua_item_write(lua_State *state, int fname_idx, void *ptr, int idx, int val_index);
 
+        virtual bool is_readonly() { return false; }
+
         virtual bool resize(void *ptr, int size) { return false; }
         virtual bool erase(void *ptr, int index) { return false; }
         virtual bool insert(void *ptr, int index, void *pitem) { return false; }
@@ -343,6 +345,33 @@ namespace df
         }
     };
 
+    template<class T>
+    class ro_stl_container_identity : public container_identity {
+        const char *name;
+
+    public:
+        ro_stl_container_identity(const char *name, type_identity *item, enum_identity *ienum = NULL)
+            : container_identity(sizeof(T), &allocator_fn<T>, item, ienum), name(name)
+        {}
+
+        std::string getFullName(type_identity *item) {
+            return name + container_identity::getFullName(item);
+        }
+
+        virtual bool is_readonly() { return true; }
+        virtual bool resize(void *ptr, int size) { return false; }
+        virtual bool erase(void *ptr, int size) { return false; }
+        virtual bool insert(void *ptr, int idx, void *item) { return false; }
+
+    protected:
+        virtual int item_count(void *ptr, CountMode) { return ((T*)ptr)->size(); }
+        virtual void *item_pointer(type_identity *item, void *ptr, int idx) {
+            auto iter = (*(T*)ptr).begin();
+            for (; idx > 0; idx--) ++iter;
+            return (void*)&*iter;
+        }
+    };
+
     class bit_array_identity : public bit_container_identity {
     public:
         /*
@@ -517,6 +546,10 @@ namespace df
         static container_identity *get();
     };
 
+    template<class T> struct identity_traits<std::set<T> > {
+        static container_identity *get();
+    };
+
     template<> struct identity_traits<BitArray<int> > {
         static bit_array_identity identity;
         static bit_container_identity *get() { return &identity; }
@@ -579,6 +612,13 @@ namespace df
         return &identity;
     }
 
+    template<class T>
+    inline container_identity *identity_traits<std::set<T> >::get() {
+        typedef std::set<T> container;
+        static ro_stl_container_identity<container> identity("set", identity_traits<T>::get());
+        return &identity;
+    }
+
     template<class T>
     inline bit_container_identity *identity_traits<BitArray<T> >::get() {
         static bit_array_identity identity(identity_traits<T>::get());

library/xml

@@ -1 +1 @@
-Subproject commit 9f91e74767b4d583b580d46e16143216ba62ae66
+Subproject commit 1eeaa08360c39a9a2d811544c2443309adc1a8f1