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diff --git a/deps/sol2/include/sol/environment.hpp b/deps/sol2/include/sol/environment.hpp
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+++ b/deps/sol2/include/sol/environment.hpp
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+// sol3 
+
+// The MIT License (MIT)
+
+// Copyright (c) 2013-2019 Rapptz, ThePhD and contributors
+
+// Permission is hereby granted, free of charge, to any person obtaining a copy of
+// this software and associated documentation files (the "Software"), to deal in
+// the Software without restriction, including without limitation the rights to
+// use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+// the Software, and to permit persons to whom the Software is furnished to do so,
+// subject to the following conditions:
+
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+// FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+// COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+// IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+// CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+#ifndef SOL_ENVIRONMENT_HPP
+#define SOL_ENVIRONMENT_HPP
+
+#include "table.hpp"
+
+namespace sol {
+
+	template <typename base_type>
+	struct basic_environment : basic_table<base_type> {
+	private:
+		typedef basic_table<base_type> base_t;
+
+	public:
+		using base_t::lua_state;
+
+		basic_environment() noexcept = default;
+		basic_environment(const basic_environment&) = default;
+		basic_environment(basic_environment&&) = default;
+		basic_environment& operator=(const basic_environment&) = default;
+		basic_environment& operator=(basic_environment&&) = default;
+		basic_environment(const stack_reference& r)
+		: basic_environment(r.lua_state(), r.stack_index()) {
+		}
+		basic_environment(stack_reference&& r)
+		: basic_environment(r.lua_state(), r.stack_index()) {
+		}
+
+		basic_environment(lua_State* L, new_table nt)
+		: base_t(L, std::move(nt)) {
+		}
+		template <bool b>
+		basic_environment(lua_State* L, new_table t, const basic_reference<b>& fallback)
+		: basic_environment(L, std::move(t)) {
+			stack_table mt(L, new_table(0, 1));
+			mt.set(meta_function::index, fallback);
+			this->set(metatable_key, mt);
+			mt.pop();
+		}
+
+		basic_environment(env_key_t, const stack_reference& extraction_target)
+		: base_t(detail::no_safety, extraction_target.lua_state(), (stack::push_environment_of(extraction_target), -1)) {
+#if defined(SOL_SAFE_REFERENCES) && SOL_SAFE_REFERENCES
+			constructor_handler handler{};
+			stack::check<env_key_t>(this->lua_state(), -1, handler);
+#endif // Safety
+			lua_pop(this->lua_state(), 2);
+		}
+		template <bool b>
+		basic_environment(env_key_t, const basic_reference<b>& extraction_target)
+		: base_t(detail::no_safety, extraction_target.lua_state(), (stack::push_environment_of(extraction_target), -1)) {
+#if defined(SOL_SAFE_REFERENCES) && SOL_SAFE_REFERENCES
+			constructor_handler handler{};
+			stack::check<env_key_t>(this->lua_state(), -1, handler);
+#endif // Safety
+			lua_pop(this->lua_state(), 2);
+		}
+		basic_environment(lua_State* L, int index = -1)
+		: base_t(detail::no_safety, L, index) {
+#if defined(SOL_SAFE_REFERENCES) && SOL_SAFE_REFERENCES
+			constructor_handler handler{};
+			stack::check<basic_environment>(L, index, handler);
+#endif // Safety
+		}
+		basic_environment(lua_State* L, ref_index index)
+		: base_t(detail::no_safety, L, index) {
+#if defined(SOL_SAFE_REFERENCES) && SOL_SAFE_REFERENCES
+			auto pp = stack::push_pop(*this);
+			constructor_handler handler{};
+			stack::check<basic_environment>(L, -1, handler);
+#endif // Safety
+		}
+		template <typename T, meta::enable<meta::neg<meta::any_same<meta::unqualified_t<T>, basic_environment>>, meta::neg<std::is_same<base_type, stack_reference>>, meta::neg<std::is_same<lua_nil_t, meta::unqualified_t<T>>>, is_lua_reference<meta::unqualified_t<T>>> = meta::enabler>
+		basic_environment(T&& r) noexcept
+		: base_t(detail::no_safety, std::forward<T>(r)) {
+#if defined(SOL_SAFE_REFERENCES) && SOL_SAFE_REFERENCES
+			if (!is_environment<meta::unqualified_t<T>>::value) {
+				auto pp = stack::push_pop(*this);
+				constructor_handler handler{};
+				stack::check<basic_environment>(lua_state(), -1, handler);
+			}
+#endif // Safety
+		}
+		basic_environment(lua_nil_t r) noexcept
+		: base_t(detail::no_safety, r) {
+		}
+
+		template <typename T, meta::enable<is_lua_reference<meta::unqualified_t<T>>> = meta::enabler>
+		basic_environment(lua_State* L, T&& r) noexcept
+			: base_t(detail::no_safety, L, std::forward<T>(r)) {
+#if defined(SOL_SAFE_REFERENCES) && SOL_SAFE_REFERENCES
+			if (!is_environment<meta::unqualified_t<T>>::value) {
+				auto pp = stack::push_pop(*this);
+				constructor_handler handler{};
+				stack::check<basic_environment>(lua_state(), -1, handler);
+			}
+#endif // Safety
+		}
+
+		template <typename T>
+		void set_on(const T& target) const {
+			lua_State* L = target.lua_state();
+			auto pp = stack::push_pop(target);
+#if SOL_LUA_VERSION < 502
+			// Use lua_setfenv
+			this->push();
+			lua_setfenv(L, -2);
+#else
+			// Use upvalues as explained in Lua 5.2 and beyond's manual
+			this->push();
+			const char* name = lua_setupvalue(L, -2, 1);
+			if (name == nullptr) {
+				this->pop();
+			}
+#endif
+		}
+	};
+
+	template <typename T, typename E>
+	void set_environment(const basic_environment<E>& env, const T& target) {
+		env.set_on(target);
+	}
+
+	template <typename E = reference, typename T>
+	basic_environment<E> get_environment(const T& target) {
+		lua_State* L = target.lua_state();
+		auto pp = stack::pop_n(L, stack::push_environment_of(target));
+		return basic_environment<E>(L, -1);
+	}
+
+	struct this_environment {
+		optional<environment> env;
+
+		this_environment()
+		: env(nullopt) {
+		}
+		this_environment(environment e)
+		: env(std::move(e)) {
+		}
+		this_environment(const this_environment&) = default;
+		this_environment(this_environment&&) = default;
+		this_environment& operator=(const this_environment&) = default;
+		this_environment& operator=(this_environment&&) = default;
+
+		explicit operator bool() const {
+			return static_cast<bool>(env);
+		}
+
+		operator optional<environment>&() {
+			return env;
+		}
+
+		operator const optional<environment>&() const {
+			return env;
+		}
+
+		operator environment&() {
+			return env.value();
+		}
+
+		operator const environment&() const {
+			return env.value();
+		}
+	};
+
+	namespace stack {
+		template <>
+		struct unqualified_getter<env_key_t> {
+			static environment get(lua_State* L, int index, record& tracking) {
+				tracking.use(1);
+				return get_environment(stack_reference(L, raw_index(index)));
+			}
+		};
+
+		template <>
+		struct unqualified_getter<this_environment> {
+			static this_environment get(lua_State* L, int, record& tracking) {
+				tracking.use(0);
+				lua_Debug info;
+				// Level 0 means current function (this C function, which may or may not be useful for us?)
+				// Level 1 means next call frame up the stack. (Can be nothing if function called directly from C++ with lua_p/call)
+				int pre_stack_size = lua_gettop(L);
+				if (lua_getstack(L, 1, &info) != 1) {
+					if (lua_getstack(L, 0, &info) != 1) {
+						lua_settop(L, pre_stack_size);
+						return this_environment();
+					}
+				}
+				if (lua_getinfo(L, "f", &info) == 0) {
+					lua_settop(L, pre_stack_size);
+					return this_environment();
+				}
+
+				stack_reference f(L, -1);
+				environment env(env_key, f);
+				if (!env.valid()) {
+					lua_settop(L, pre_stack_size);
+					return this_environment();
+				}
+				return this_environment(std::move(env));
+			}
+		};
+	} // namespace stack
+} // namespace sol
+
+#endif // SOL_ENVIRONMENT_HPP