Update sample code in main(), fix the rest as required

include/wrenpp/def_configuration.hpp

@@ -29,6 +29,5 @@ namespace wren {
 	public:
 		static void write_fn (VM*, const char* text);
 		static void error_fn (VM*, ErrorType, const char* module, int line, const char* msg);
-		foreign_method_t foreign_method_fn (VM* vm, const char* module, const char* class_name, bool is_static, const char* signature);
 	};
 } //namespace wren

include/wrenpp/vm_fun.hpp

@@ -189,7 +189,7 @@ namespace wren {
 		const constexpr char dummy_name_buff[N] = {0};
 		const constexpr auto params = dhandy::bt::string<N, char>(dummy_name_buff) +
 			dhandy::bt::make_string("(") +
-			((static_cast<void>(args), dhandy::bt::make_string(",_")) + ...).template substr<1>() +
+			((static_cast<void>(args), dhandy::bt::make_string(",_")) + ... + dhandy::bt::make_string("")).template substr<1>() +
 			dhandy::bt::make_string(")");
 		;
 		char cat_buff[params.size() + 1];

meson.build

@@ -63,7 +63,7 @@ wrenpp_dep = declare_dependency(
   include_directories: public_incl,
 )
 
-executable(meson.project_name(),
+executable(meson.project_name() + 'sample',
   'src/main.cpp',
   dependencies: wrenpp_dep,
   install: false,

src/main.cpp

@@ -17,44 +17,79 @@
 
 #include "wrenpp/vm_fun.hpp"
 #include "wrenpp/def_configuration.hpp"
-#include <iostream>
 #include <chrono>
 #include <thread>
+#include <unistd.h>
+
+#if defined(__GNU_LIBRARY__) && ((__GLIBC__ == 2 && __GLIBC_MINOR__ >= 17) || __GLIBC__ > 2)
+#	define HasSecureGetenv
+#endif
 
 namespace {
 	const constexpr char g_script[] = ""
-R"(class Math {
-	construct new() {}
-	foreign add(a, b)
+R"script(class User {
+	construct new(nm) {
+		_name = nm
+	}
 
-	static sum_params(a,b) {
-		return a + b
+	foreign static get_env(name)
+
+	greet() {
+		System.print("Hello %(_name), from wren script!")
 	}
 }
-System.print("I am running in a VM!")
-var myvar = Math.new()
-var name = "some_test"
-var number = 123
-myvar.add(5, 6)
-System.print("Script done")
-)";
 
+var the_user = User.new(User.get_env("USER"))
+)script";
+
+const char* raw_fetch_env (const char* name) noexcept {
+	if (not name)
+		return nullptr;
+
+#if defined(HasSecureGetenv)
+	const char* const val_ptr = secure_getenv(name);
+#else
+	const char* const val_ptr = getenv(name);
+#endif
+
+	return val_ptr;
+}
+
+void user_get_env (wren::VM* vm) {
+	set(*vm, 0, raw_fetch_env(wren::get<const char*>(*vm, 1)));
+}
+
+class MyConfig : public wren::DefConfiguration {
+public:
+	wren::foreign_method_t foreign_method_fn (
+		wren::VM* vm,
+		const char* module_ptr,
+		const char* class_name_ptr,
+		bool is_static,
+		const char* signature_ptr
+	) {
+		//std::cout << "VM " << vm << " requested foreign method " << class_name << "::" << signature << " in module " << module << "\n";
+		std::string_view module(module_ptr);
+		std::string_view class_name(class_name_ptr);
+		std::string_view signature(signature_ptr);
+		if ("User" == class_name and "main" == module and "get_env(_)" == signature)
+			return &user_get_env;
+
+		return nullptr;
+	}
+};
 } //unnamed namespace
 
 int main() {
-	typedef wren::ModuleAndName MN;
-	using wren::variables;
+	//typedef wren::ModuleAndName MN;
 
-	std::cout << "hello world\n";
-	wren::DefConfiguration config;
+	MyConfig config;
 	wren::VM vm(&config);
-	vm.interpret("my_module", g_script);
+	vm.interpret("main", g_script);
 
-	auto vars = variables<std::string, int>(vm, MN{"my_module", "name"}, MN{"my_module","number"});
-	std::cout << "name = \"" << std::get<0>(vars) << "\", number = " << std::get<1>(vars) << '\n';
-	const int sum = wren::call<int>(vm, {"my_module", "Math"}, "sum_params", MN{"my_module", "number"}, 90);
-	std::cout << "wren method returned " << sum << " (expected " << std::get<1>(vars) + 90 << ")\n";
+	wren::call<void>(vm, {"main", "the_user"}, "greet");
 
+	std::cout << "Quitting in 1 sec" << std::endl;
 	std::this_thread::sleep_for(std::chrono::milliseconds(1000));
 	return 0;
 }

src/wren/def_configuration.cpp

@@ -19,10 +19,6 @@
 #include <iostream>
 
 namespace wren {
-	void test (VM* vm) {
-		std::cout << "VM " << vm << " invoked foreign method!\n";
-	}
-
 	void DefConfiguration::write_fn (VM*, const char* text) {
 		std::cout << text;
 	}
@@ -30,9 +26,4 @@ namespace wren {
 	void DefConfiguration::error_fn (VM*, ErrorType type, const char* module, int line, const char* message) {
 		std::cerr << "Wren error: " << message << " in " << module << ':' << line << '\n';
 	}
-
-	foreign_method_t DefConfiguration::foreign_method_fn (VM* vm, const char* module, const char* class_name, bool is_static, const char* signature) {
-		std::cout << "VM " << vm << " requested foreign method " << class_name << "::" << signature << " in module " << module << "\n";
-		return &test;
-	}
 } //namespace wren

src/wren/vm_fun.cpp

@@ -34,8 +34,8 @@ namespace wren {
 		return {ptr.first, static_cast<std::size_t>(ptr.second)};
 	}
 
-	template<> std::string get (VM& vm, int slot_num) {
-		return {vm.slot_string(slot_num)};
+	template<> const char* get (VM& vm, int slot_num) {
+		return vm.slot_string(slot_num);
 	}
 
 	template <> double get (VM& vm, int slot_num) {
@@ -54,6 +54,10 @@ namespace wren {
 		return static_cast<int>(vm.slot_double(slot_num));
 	}
 
+	template<> std::string get (VM& vm, int slot_num) {
+		return {vm.slot_string(slot_num)};
+	}
+
 	template <> std::string_view get (VM& vm, int slot_num) {
 		auto arr = get<std::pair<const char*, int>>(vm, slot_num);
 		return std::string_view{arr.first, static_cast<std::size_t>(arr.second)};