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#define SOL_ALL_SAFETIES_ON 1
#include <sol/sol.hpp>
#include "assert.hpp"
#include <iostream>
int main(int, char**) {
sol::state lua;
lua.open_libraries(sol::lib::base);
// Environments can set on functions (scripts), userdata and threads
// let's look at functions
lua.script("f = function() return test end");
sol::function f = lua["f"];
sol::environment env_f(lua, sol::create);
env_f["test"] = 31;
sol::set_environment(env_f, f);
// the function returns the value from the environment table
int result = f();
c_assert(result == 31);
// You can also protect from variables
// being set without the 'local' specifier
lua.script("g = function() test = 5 end");
sol::function g = lua["g"];
sol::environment env_g(lua, sol::create);
env_g.set_on(g); // same as set_environment
g();
// the value can be retrieved from the env table
int test = env_g["test"];
c_assert(test == 5);
// the global environment
// is not polluted at all, despite both functions being used and set
sol::object global_test = lua["test"];
c_assert(!global_test.valid());
// You can retrieve environments in C++
// and check the environment of functions
// gotten from Lua
// get the environment from any sol::reference-styled type,
// including sol::object, sol::function, sol::table, sol::userdata ...
lua.set_function("check_f_env",
// capture necessary variable in C++ lambda
[&env_f]( sol::object target ) {
// pull out the environment from func using
// sol::env_key constructor
sol::environment target_env(sol::env_key, target);
int test_env_f = env_f["test"];
int test_target_env = target_env["test"];
// the environment for f the one gotten from `target`
// are the same
c_assert(test_env_f == test_target_env);
c_assert(test_env_f == 31);
c_assert(env_f == target_env);
}
);
lua.set_function("check_g_env",
[&env_g](sol::function target) {
// equivalent:
sol::environment target_env = sol::get_environment(target);
int test_env_g = env_g["test"];
int test_target_env = target_env["test"];
c_assert(test_env_g == test_target_env);
c_assert(test_env_g == 5);
c_assert(env_g == target_env);
}
);
lua.script("check_f_env(f)");
lua.script("check_g_env(g)");
return 0;
}
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