diff --git a/luprex/cpp/gui.cpp b/luprex/cpp/gui.cpp
index c5477553..fe4a6c75 100644
--- a/luprex/cpp/gui.cpp
+++ b/luprex/cpp/gui.cpp
@@ -10,3 +10,18 @@ void Gui::add_menu_item(const std::string &id, const std::string &label) {
     elts_.push_back(elt);
 }
 
+LuaDefine(gui_create, "c") {
+    LuaRet lgui;
+    LuaStack LS(L, lgui);
+    LS.newpointer<Gui>(lgui, new Gui, true);
+    return LS.result();
+}
+
+LuaDefine(gui_add_menu_item, "c") {
+    LuaArg lgui, lid;
+    LuaStack LS(L, lgui, lid);
+    Gui *gui = LS.ckuserdata<Gui>(lgui);
+    std::string id = LS.ckstring(lid);
+    gui->add_menu_item(id, id);
+    return LS.result();
+}
diff --git a/luprex/cpp/luaconsole.cpp b/luprex/cpp/luaconsole.cpp
index c3733f22..88a78ce6 100644
--- a/luprex/cpp/luaconsole.cpp
+++ b/luprex/cpp/luaconsole.cpp
@@ -48,34 +48,23 @@ void LuaConsole::add(std::string line) {
     raw_input_ += line;
     raw_input_ += '\n';
     lines_ += 1;
-    char cmd = raw_input_[0];
 
-    // All commands are a single character.
-    if ((raw_input_[1] != ' ')&&(raw_input_[1] != '\n')) {
-        action_ = DO_SYNTAX;
-        syntax_ = "Commands are a single character followed by arguments";
-        return;
-    }
-
-    // Analyze non-lua commands.
-    if ((cmd != 'r') && (cmd != 'l')) {
-        lua_expression_ = "";
-        if (lines_ == 1) {
+    // Try to interpret it as a special command.
+    if (lines_ == 1) {
+        split_words();
+        if ((words_.size() >= 1)&&(words_[0].size() == 1)) {
             action_ = DO_COMMAND;
-            split_words();
-        } else {
-            action_ = DO_SYNTAX;
-            syntax_ = "slash command has more than one line";
+            return;
         }
-        return;
     }
-    
+    words_.clear();
+
     // Strip the leading punctuation from lua commands.
     std::string partial;
-    if (cmd == 'r') {
-        partial = std::string("return ") + raw_input_.substr(2);
+    if (raw_input_[0] == '=') {
+        partial = std::string("return ") + raw_input_.substr(1);
     } else {
-        partial = raw_input_.substr(2);
+        partial = raw_input_;
     }
 
     // Analyze lua expressions.
diff --git a/luprex/cpp/luaconsole.hpp b/luprex/cpp/luaconsole.hpp
index 4c2bdeeb..0af201e4 100644
--- a/luprex/cpp/luaconsole.hpp
+++ b/luprex/cpp/luaconsole.hpp
@@ -32,7 +32,7 @@ class LuaConsole {
 public:
     enum {
         DO_NOTHING,  // We need more input text.
-        DO_COMMAND,  // We have a valid non-lua command.
+        DO_COMMAND,  // We have a valid slash command.
         DO_LUA,      // We have a valid lua expression.
         DO_SYNTAX,   // We have a syntax error.
     };
diff --git a/luprex/cpp/luastack.cpp b/luprex/cpp/luastack.cpp
index 4d1bb38f..0c4fee30 100644
--- a/luprex/cpp/luastack.cpp
+++ b/luprex/cpp/luastack.cpp
@@ -1,4 +1,5 @@
 #include "luastack.hpp"
+#include "util.hpp"
 #include <iostream>
 
 LuaSpecial LuaRegistry(LUA_REGISTRYINDEX);
@@ -24,11 +25,10 @@ int LuaStack::collect_tagged_pointer(lua_State *L) {
     if (p==0) {
         luaL_error(L, "lua deleter function received a non-userdata");
     }
-    if (p->ptr == 0) {
-        luaL_error(L, "lua object already deleted");
+    if (p->ptr != 0) {
+        p->del(p->ptr);
+        p->ptr = 0;
     }
-    p->del(p->ptr);
-    p->ptr = 0;
     return 0;
 }
 
@@ -37,7 +37,7 @@ void LuaStack::register_all_userdata(lua_State *L) {
     LuaStack LS(L, tab, lud);
     auto regs = LuaFunctionReg::all();
     for (const LuaFunctionReg *r : regs) {
-        const std::string &name = r->get_name();
+        const std::string &name = util::tolower(r->get_name());
         lua_CFunction tag = r->get_func();
         std::string mode = r->get_mode();
         if (mode.find('t') != std::string::npos) { // Register type
@@ -209,4 +209,18 @@ void LuaStack::check_nret(int xnret, int otop, int nret) const {
         luaL_error(L_, "expected %d return values", xnret);
     }
 }
-    
\ No newline at end of file
+
+LuaDefine(system_type, "f") {
+    LuaArg obj;
+    LuaRet tname;
+    LuaVar mt;
+    LuaStack LS(L, obj, tname, mt);
+    int type = LS.type(obj);
+    if (type == LUA_TUSERDATA) {
+        LS.getmetatable(mt, obj);
+        LS.getfield(tname, mt, "type");
+    } else {
+        LS.set(tname, lua_typename(L, type));
+    }
+    return LS.result();
+}
diff --git a/luprex/cpp/util.cpp b/luprex/cpp/util.cpp
index f0c0ae0d..3f902cbb 100644
--- a/luprex/cpp/util.cpp
+++ b/luprex/cpp/util.cpp
@@ -12,6 +12,20 @@
 
 namespace util {
 
+std::string tolower(std::string input) {
+    for (int i = 0; i < int(input.size()); i++) {
+        input[i] = std::tolower(input[i]);
+    }
+    return input;
+}
+
+std::string toupper(std::string input) {
+    for (int i = 0; i < int(input.size()); i++) {
+        input[i] = std::toupper(input[i]);
+    }
+    return input;
+}
+
 int64_t strtoint(const std::string &value, int64_t errval) {
     char *endptr;
     int64_t result = strtoll(value.c_str(), &endptr, 10);
diff --git a/luprex/cpp/util.hpp b/luprex/cpp/util.hpp
index 2db747d6..70bbafec 100644
--- a/luprex/cpp/util.hpp
+++ b/luprex/cpp/util.hpp
@@ -14,6 +14,10 @@ namespace util {
 using stringvec = std::vector<std::string>;
 using stringset = std::set<std::string>;
 
+// String to lowercase/uppercase
+std::string tolower(std::string input);
+std::string toupper(std::string input);
+
 // String to integer.  Returns errval if the number is not parseable.
 int64_t strtoint(const std::string &value, int64_t errval);