add a new example, add a note, adjust for LuaJIT Beta3 and beyond (hopefully it doesn't flip its crap: will have to warn suers....)

.gitignore

@@ -48,7 +48,7 @@ lua-5.2.4/
 lua-5.2.2/
 lua-5.2.3/
 lua-5.1.5/
-luajit-2.0.4/
+luajit-2.0.5/
 luajit-2.0.3/
 include/
 liblua.a
@@ -65,13 +65,13 @@ single/sol.hpp
 lua53.dll
 main.exe
 main.o
-lua-5.3.3/
+lua-5.3.4/
 main.lua
 LuaJIT-2.1.0/
-lua-5.3.3-cxx/
+lua-5.3.4-cxx/
-lua-5.3.3.vcxproj-cxx.filters
+lua-5.3.4.vcxproj-cxx.filters
 sol.pyproj
-lua-5.3.3.dll
+lua-5.3.4.dll
 main.ilk
 main.pdb
 lua-5.3.4-cxx/

examples/environment_snooping.cpp

@@ -0,0 +1,72 @@
+#define SOL_CHECK_ARGUMENTS
+#include <sol.hpp>
+
+#include <cassert>
+#include <iostream>
+
+// NOTE:
+// THIS IS A LOW-LEVEL EXAMPLE, using pieces of sol2
+// to facilitate better usage
+// If you need to do this often, you can copy this code and paste it in a utility function for yourself
+// so you can grab the environment whenever you need to
+
+void some_function_called_by_sol2(sol::this_state ts) {
+	lua_State* L = ts;
+
+	lua_Debug info;
+	// Level 0 means current function (this C function, which is useless for our purposes)
+	// Level 1 means next call frame up the stack. This is probably the environment we're looking for?
+	int level = 1;
+	int pre_stack_size = lua_gettop(L);
+	if (lua_getstack(L, level, &info) != 1) {
+		// failure: call it quits
+		std::cout << "error: unable to traverse the stack" << std::endl;
+		lua_settop(L, pre_stack_size);
+		return;
+	}
+	// the "f" identifier is the most important here
+	// it pushes the function running at `level` onto the stack:
+	// we can get the environment from this
+	// the rest is for printing / debugging purposes
+	if (lua_getinfo(L, "fnluS", &info) == 0) {
+		// failure?
+		std::cout << "error: unable to get stack information" << std::endl;
+		lua_settop(L, pre_stack_size);
+		return;
+	}
+
+	// Okay, so all the calls worked.
+	// Print out some information about this "level"
+	std::cout << "[" << level << "] " << info.short_src << ":" << info.currentline
+		<< " -- " << (info.name ? info.name : "<unknown>") << "[" << info.what << "]" << std::endl;
+
+	// Grab the function off the top of the stack
+	// remember: -1 means top, -2 means 1 below the top, and so on...
+	// 1 means the very bottom of the stack, 
+	// 2 means 1 more up, and so on to the top value...
+	sol::function f(L, -1);
+	// The environment can now be ripped out of the function
+	sol::environment env(sol::env_key, f);
+	if (!env.valid()) {
+		std::cout << "error: no environment to get" << std::endl;
+		lua_settop(L, pre_stack_size);
+		return;
+	}
+	sol::state_view lua(L);
+	sol::environment freshenv = lua["freshenv"];
+	bool is_same_env = freshenv == env;
+	std::cout << "env == freshenv : " << is_same_env << std::endl;
+}
+
+int main() {
+	std::cout << "=== environment snooping example ===" << std::endl;
+	sol::state lua;
+
+	sol::environment freshenv(lua, sol::create, lua.globals());
+	lua["freshenv"] = freshenv;
+	lua.set_function("f", some_function_called_by_sol2);
+
+	lua.script("f()", freshenv);
+
+	return 0;
+}

examples/self_from_lua.cpp

@@ -3,6 +3,11 @@
 
 #include <cassert>
 
+// NOTE:
+// There are TWO ways to retrieve the "this"
+// object from calls, when it comes to constructors and regular member functions
+// please pay attention to both: this is a low-level operation!
+
 int main() {
 	struct thing {
 

single/sol/sol.hpp

@@ -20,8 +20,8 @@
 // CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 // This file was generated with a script.
-// Generated 2017-05-04 07:17:19.632331 UTC
+// Generated 2017-05-07 14:16:38.081474 UTC
-// This header was generated with sol v2.17.1 (revision 7b78558)
+// This header was generated with sol v2.17.1 (revision 5bc5def)
 // https://github.com/ThePhD/sol2
 
 #ifndef SOL_SINGLE_INCLUDE_HPP
@@ -1111,8 +1111,15 @@ inline int luaL_loadbufferx(lua_State* L, const char* buff, size_t size, const c
 #define lua_pushglobaltable(L) \
   lua_pushvalue(L, LUA_GLOBALSINDEX)
 
+#ifndef SOL_LUAJIT
 #define luaL_newlib(L, l) \
   (lua_newtable((L)),luaL_setfuncs((L), (l), 0))
+#else
+#if SOL_LUAJIT_VERSION < 20100
+#define luaL_newlib(L, l) \
+  (lua_newtable((L)),luaL_setfuncs((L), (l), 0))
+#endif // LuaJIT-2.1.0-beta3 added this in itself
+#endif // LuaJIT Compatibility
 
 void luaL_checkversion(lua_State *L);
 

sol/compatibility/5.x.x.h

@@ -33,8 +33,15 @@
 #define lua_pushglobaltable(L) \
   lua_pushvalue(L, LUA_GLOBALSINDEX)
 
+#ifndef SOL_LUAJIT
 #define luaL_newlib(L, l) \
   (lua_newtable((L)),luaL_setfuncs((L), (l), 0))
+#else
+#if SOL_LUAJIT_VERSION < 20100
+#define luaL_newlib(L, l) \
+  (lua_newtable((L)),luaL_setfuncs((L), (l), 0))
+#endif // LuaJIT-2.1.0-beta3 added this in itself
+#endif // LuaJIT Compatibility
 
 void luaL_checkversion(lua_State *L);