diff --git a/include/library/lua-base.hpp b/include/library/lua-base.hpp
index 0902bd12..8ccbdbaf 100644
--- a/include/library/lua-base.hpp
+++ b/include/library/lua-base.hpp
@@ -318,6 +318,20 @@ public:
 			(stringfmt() << "argument #" << argindex << " to " << fname << " must be string").throwex();
 		return std::string(f, f + len);
 	}
+/**
+ * Read slot as string.
+ *
+ * Parameter argindex: The stack index.
+ * Returns: The string.
+ */
+	std::string as_string(int argindex)
+	{
+		if(isnone(argindex)) return "(none)";
+		size_t len;
+		const char* f = lua_tolstring(lua_handle, argindex, &len);
+		if(!f) return "(null)";
+		return std::string(f, f + len);
+	}
 /**
  * Get a boolean argument.
  *
diff --git a/src/lua/ibind.cpp b/src/lua/ibind.cpp
index 7abe08e8..bdf5664f 100644
--- a/src/lua/ibind.cpp
+++ b/src/lua/ibind.cpp
@@ -37,7 +37,7 @@ public:
 		int r = L.pcall(1, 0, 0);
 		std::string err;
 		if(r == LUA_ERRRUN)
-			err = L.get_string(-1, "Lua command callback");
+			err = L.as_string(-1);
 		else if(r == LUA_ERRMEM)
 			err = "Out of memory";
 		else if(r == LUA_ERRERR)
diff --git a/src/lua/lua.cpp b/src/lua/lua.cpp
index 519beceb..71f5ed93 100644
--- a/src/lua/lua.cpp
+++ b/src/lua/lua.cpp
@@ -533,8 +533,7 @@ bool lua_state::run_lua_fragment()
 		return false;
 	int t = L.load(read_lua_fragment, &luareader_fragment, "run_lua_fragment", "t");
 	if(t == LUA_ERRSYNTAX) {
-		messages << "Can't run Lua: Internal syntax error: " << L.tostring(-1)
-			<< std::endl;
+		messages << "Can't run Lua: Internal syntax error: " << L.as_string(-1) << std::endl;
 		L.pop(1);
 		return false;
 	}
@@ -547,7 +546,9 @@ bool lua_state::run_lua_fragment()
 	int r = L.pcall(0, 0, 0);
 	recursive_flag = false;
 	if(r == LUA_ERRRUN) {
-		messages << "Error running Lua hunk: " << L.tostring(-1)  << std::endl;
+		auto msgptr = L.tostring(-1);
+		if(!msgptr) msgptr = "(null)";
+		messages << "Error running Lua hunk: " << L.as_string(-1) << std::endl;
 		L.pop(1);
 		result = false;
 	}
diff --git a/src/lua/memory.cpp b/src/lua/memory.cpp
index c7b7b4fd..36615eb0 100644
--- a/src/lua/memory.cpp
+++ b/src/lua/memory.cpp
@@ -178,7 +178,7 @@ namespace
 		if(!ret) return;
 		switch(ret) {
 		case LUA_ERRRUN:
-			messages << "Error in Lua memory callback: " << L.get_string(-1, "errhnd") << std::endl;
+			messages << "Error in Lua memory callback: " << L.as_string(-1) << std::endl;
 			L.pop(1);
 			return;
 		case LUA_ERRMEM: