4 files changed, 237 insertions, 74 deletions

diff --git a/src/MoonP/moon_ast.h b/src/MoonP/moon_ast.h
index dd01165..9fab215 100644
--- a/src/MoonP/moon_ast.h
+++ b/src/MoonP/moon_ast.h
@@ -500,18 +500,28 @@ AST_NODE(ClassDecl)
         AST_MEMBER(ClassDecl, &name, &extend, &body)
 AST_END(ClassDecl)
 
-AST_NODE(export_values)
+AST_NODE(global_values)
         ast_ptr<true, NameList_t> nameList;
         ast_ptr<false, ExpListLow_t> valueList;
-        AST_MEMBER(export_values, &nameList, &valueList)
-AST_END(export_values)
+        AST_MEMBER(global_values, &nameList, &valueList)
+AST_END(global_values)
 
-AST_LEAF(export_op)
-AST_END(export_op)
+AST_LEAF(global_op)
+AST_END(global_op)
+
+AST_NODE(Global)
+        ast_sel<true, ClassDecl_t, global_op_t, global_values_t> item;
+        AST_MEMBER(Global, &item)
+AST_END(Global)
+
+AST_LEAF(export_default)
+AST_END(export_default)
 
 AST_NODE(Export)
-        ast_sel<true, ClassDecl_t, export_op_t, export_values_t> item;
-        AST_MEMBER(Export, &item)
+        ast_ptr<false, export_default_t> def;
+        ast_sel<true, ExpList_t, Exp_t> target;
+        ast_ptr<false, Assign_t> assign;
+        AST_MEMBER(Export, &def, &target, &assign)
 AST_END(Export)
 
 AST_NODE(FnArgDef)
@@ -601,7 +611,7 @@ AST_END(BreakLoop)
 
 AST_NODE(Statement)
         ast_sel<true, Import_t, While_t, For_t, ForEach_t,
-                Return_t, Local_t, Export_t, BreakLoop_t,
+                Return_t, Local_t, Global_t, Export_t, BreakLoop_t,
                 Backcall_t, ExpListAssign_t> content;
         ast_ptr<false, statement_appendix_t> appendix;
         AST_MEMBER(Statement, &content, &appendix)
diff --git a/src/MoonP/moon_compiler.cpp b/src/MoonP/moon_compiler.cpp
index 83b91e6..1adfec9 100644
--- a/src/MoonP/moon_compiler.cpp
+++ b/src/MoonP/moon_compiler.cpp
@@ -32,7 +32,7 @@ inline std::string s(std::string_view sv) {
 }
 
 const char* moonScriptVersion() {
-        return "0.5.0-r0.1.5";
+        return "0.5.0-r0.2.0";
 }
 
 class MoonCompilerImpl {
@@ -45,7 +45,10 @@ public:
                         try {
                                 str_list out;
                                 pushScope();
-                                transformBlock(_info.node.to<File_t>()->block, out, config.implicitReturnRoot ? ExpUsage::Return : ExpUsage::Common);
+                                enableReturn.push(_info.moduleName.empty());
+                                transformBlock(_info.node.to<File_t>()->block, out,
+                                        config.implicitReturnRoot ? ExpUsage::Return : ExpUsage::Common,
+                                        nullptr, true);
                                 popScope();
                                 if (config.lintGlobalVariable) {
                                         globals = std::make_unique<std::list<GlobalVar>>();
@@ -86,6 +89,7 @@ private:
         MoonParser _parser;
         ParseInfo _info;
         int _indentOffset = 0;
+        std::stack<bool> enableReturn;
         std::list<std::unique_ptr<input>> _codeCache;
         std::stack<std::string> _withVars;
         std::stack<std::string> _continueVars;
@@ -98,16 +102,16 @@ private:
                 Capital = 1,
                 Any = 2
         };
-        enum class ExportMode {
+        enum class GlobalMode {
                 None = 0,
                 Capital = 1,
                 Any = 2
         };
         struct Scope {
-                ExportMode mode = ExportMode::None;
+                GlobalMode mode = GlobalMode::None;
                 std::unique_ptr<std::unordered_set<std::string>> vars;
                 std::unique_ptr<std::unordered_set<std::string>> allows;
-                std::unique_ptr<std::unordered_set<std::string>> exports;
+                std::unique_ptr<std::unordered_set<std::string>> globals;
         };
         std::list<Scope> _scopes;
         static const std::string Empty;
@@ -153,11 +157,11 @@ private:
 
         bool isDefined(const std::string& name) const {
                 bool isDefined = false;
-                int mode = int(std::isupper(name[0]) ? ExportMode::Capital : ExportMode::Any);
+                int mode = int(std::isupper(name[0]) ? GlobalMode::Capital : GlobalMode::Any);
                 const auto& current = _scopes.back();
                 if (int(current.mode) >= mode) {
-                        if (current.exports) {
-                                if (current.exports->find(name) != current.exports->end()) {
+                        if (current.globals) {
+                                if (current.globals->find(name) != current.globals->end()) {
                                         isDefined = true;
                                         current.vars->insert(name);
                                 }
@@ -202,17 +206,17 @@ private:
                 scope.allows = std::make_unique<std::unordered_set<std::string>>();
         }
 
-        void markVarExported(ExportMode mode, bool specified) {
+        void markVarGlobal(GlobalMode mode, bool specified) {
                 auto& scope = _scopes.back();
                 scope.mode = mode;
-                if (specified && !scope.exports) {
-                        scope.exports = std::make_unique<std::unordered_set<std::string>>();
+                if (specified && !scope.globals) {
+                        scope.globals = std::make_unique<std::unordered_set<std::string>>();
                 }
         }
 
-        void addExportedVar(const std::string& name) {
+        void addGlobalVar(const std::string& name) {
                 auto& scope = _scopes.back();
-                scope.exports->insert(name);
+                scope.globals->insert(name);
         }
 
         void addToAllowList(const std::string& name) {
@@ -457,6 +461,20 @@ private:
                 return Empty;
         }
 
+        Variable_t* variableFrom(Exp_t* exp) {
+                BLOCK_START
+                auto value = singleValueFrom(exp);
+                BREAK_IF(!value);
+                auto chainValue = value->getByPath<ChainValue_t>();
+                BREAK_IF(!chainValue);
+                BREAK_IF(chainValue->items.size() != 1);
+                auto callable = ast_cast<Callable_t>(chainValue->items.front());
+                BREAK_IF(!callable);
+                return callable->item.as<Variable_t>();
+                BLOCK_END
+                return nullptr;
+        }
+
         bool isAssignable(const node_container& chainItems) const {
                 if (chainItems.size() == 1) {
                          auto firstItem = chainItems.back();
@@ -647,6 +665,7 @@ private:
                         case id<ForEach_t>(): transformForEach(static_cast<ForEach_t*>(content), out); break;
                         case id<Return_t>(): transformReturn(static_cast<Return_t*>(content), out); break;
                         case id<Local_t>(): transformLocal(static_cast<Local_t*>(content), out); break;
+                        case id<Global_t>(): transformGlobal(static_cast<Global_t*>(content), out); break;
                         case id<Export_t>(): transformExport(static_cast<Export_t*>(content), out); break;
                         case id<BreakLoop_t>(): transformBreakLoop(static_cast<BreakLoop_t*>(content), out); break;
                         case id<ExpListAssign_t>(): {
@@ -693,7 +712,7 @@ private:
                                                         break;
                                                 }
                                         }
-                                        throw std::logic_error(_info.errorMessage("Expression list must appear at the end of body or block."sv, expList));
+                                        throw std::logic_error(_info.errorMessage("Expression list is not supported here."sv, expList));
                                 }
                                 break;
                         }
@@ -749,8 +768,8 @@ private:
                 return preDefs;
         }
 
-        str_list transformAssignDefs(ExpList_t* expList) {
-                str_list preDefs;
+        str_list transformAssignDefs(ExpList_t* expList, bool markDefined = true) {
+                str_list defs;
                 for (auto exp_ : expList->exprs.objects()) {
                         auto exp = static_cast<Exp_t*>(exp_);
                         if (auto value = singleValueFrom(exp)) {
@@ -766,8 +785,8 @@ private:
                                                 if (self->name.is<self_t>()) name = "self"sv;
                                         }
                                         BREAK_IF(name.empty());
-                                        if (addToScope(name)) {
-                                                preDefs.push_back(name);
+                                        if (!markDefined || addToScope(name)) {
+                                                defs.push_back(name);
                                         }
                                         BLOCK_END
                                 }
@@ -775,7 +794,7 @@ private:
                                 throw std::logic_error(_info.errorMessage("Left hand expression is not assignable."sv, exp));
                         }
                 }
-                return preDefs;
+                return defs;
         }
 
         std::string getPredefine(const str_list& defs) {
@@ -1650,6 +1669,7 @@ private:
         }
 
         void transformFunLit(FunLit_t* funLit, str_list& out) {
+                enableReturn.push(true);
                 str_list temp;
                 bool isFatArrow = _parser.toString(funLit->arrow) == "=>"sv;
                 pushScope();
@@ -1698,6 +1718,7 @@ private:
                         }
                 }
                 out.push_back(clearBuf());
+                enableReturn.pop();
         }
 
         void transformBody(Body_t* body, str_list& out, ExpUsage usage, ExpList_t* assignList = nullptr) {
@@ -1711,7 +1732,7 @@ private:
                 }
         }
 
-        void transformBlock(Block_t* block, str_list& out, ExpUsage usage, ExpList_t* assignList = nullptr) {
+        void transformBlock(Block_t* block, str_list& out, ExpUsage usage, ExpList_t* assignList = nullptr, bool isRoot = false) {
                 const auto& nodes = block->statements.objects();
                 LocalMode mode = LocalMode::None;
                 Local_t* any = nullptr, *capital = nullptr;
@@ -1768,7 +1789,7 @@ private:
                                                                 args->swap(a, arg);
                                                                 findPlaceHolder = true;
                                                         } else {
-                                                                throw std::logic_error(_info.errorMessage("backcall placeholder can be used only in one place."sv, a));
+                                                                throw std::logic_error(_info.errorMessage("Backcall placeholder can be used only in one place."sv, a));
                                                         }
                                                 }
                                         }
@@ -1792,9 +1813,10 @@ private:
                                         auto expListAssign = x->new_ptr<ExpListAssign_t>();
                                         expListAssign->expList.set(expList);
                                         newStmt->content.set(expListAssign);
+                                        newStmt->appendix.set(stmt->appendix);
                                         newBlock->statements.push_back(newStmt);
                                 }
-                                transformBlock(newBlock, out, usage, assignList);
+                                transformBlock(newBlock, out, usage, assignList, isRoot);
                                 return;
                         }
                         if (auto local = stmt->content.as<Local_t>()) {
@@ -1838,6 +1860,15 @@ private:
                                                                         }
                                                                 }
                                         }
+                                        if (info.second) {
+                                                auto defs = transformAssignDefs(info.second->expList, false);
+                                                for (const auto& def : defs) {
+                                                        if (std::isupper(def[0]) && capital) { capital->decls.push_back(def);
+                                                        } else if (any) {
+                                                                any->decls.push_back(def);
+                                                        }
+                                                }
+                                        }
                                         BLOCK_START
                                         auto assign = assignment->action.as<Assign_t>();
                                         BREAK_IF(!assign);
@@ -1865,10 +1896,14 @@ private:
                                 }
                         }
                 }
+                if (isRoot && !_info.moduleName.empty()) {
+                        block->statements.push_front(toAst<Statement_t>(_info.moduleName + s(_info.exportDefault ? "=nil"sv : "={}"sv), block));
+                }
                 switch (usage) {
                         case ExpUsage::Closure:
                         case ExpUsage::Return: {
                                 BLOCK_START
+                                BREAK_IF(isRoot && !_info.moduleName.empty());
                                 BREAK_IF(nodes.empty());
                                 auto last = static_cast<Statement_t*>(nodes.back());
                                 auto x = last;
@@ -1920,9 +1955,17 @@ private:
                 } else {
                         out.push_back(Empty);
                 }
+                if (isRoot && !_info.moduleName.empty()) {
+                        out.back().append(indent() + s("return "sv) + _info.moduleName + nlr(block));
+                }
         }
 
         void transformReturn(Return_t* returnNode, str_list& out) {
+                if (!enableReturn.top()) {
+                        ast_node* target = returnNode->valueList.get();
+                        if (!target) target = returnNode;
+                        throw std::logic_error(_info.errorMessage("Illegal return statement here."sv, target));
+                }
                 if (auto valueList = returnNode->valueList.get()) {
                         if (valueList->exprs.size() == 1) {
                                 auto exp = static_cast<Exp_t*>(valueList->exprs.back());
@@ -3797,33 +3840,33 @@ private:
                 out.push_back(_parser.toString(const_value));
         }
 
-        void transformExport(Export_t* exportNode, str_list& out) {
-                auto x = exportNode;
-                auto item = exportNode->item.get();
+        void transformGlobal(Global_t* global, str_list& out) {
+                auto x = global;
+                auto item = global->item.get();
                 switch (item->getId()) {
                         case id<ClassDecl_t>(): {
                                 auto classDecl = static_cast<ClassDecl_t*>(item);
                                 if (classDecl->name && classDecl->name->item->getId() == id<Variable_t>()) {
-                                        markVarExported(ExportMode::Any, true);
-                                        addExportedVar(_parser.toString(classDecl->name->item));
+                                        markVarGlobal(GlobalMode::Any, true);
+                                        addGlobalVar(_parser.toString(classDecl->name->item));
                                 }
                                 transformClassDecl(classDecl, out, ExpUsage::Common);
                                 break;
                         }
-                        case id<export_op_t>():
+                        case id<global_op_t>():
                                 if (_parser.toString(item) == "*"sv) {
-                                        markVarExported(ExportMode::Any, false);
+                                        markVarGlobal(GlobalMode::Any, false);
                                 } else {
-                                        markVarExported(ExportMode::Capital, false);
+                                        markVarGlobal(GlobalMode::Capital, false);
                                 }
                                 break;
-                        case id<export_values_t>(): {
-                                markVarExported(ExportMode::Any, true);
-                                auto values = exportNode->item.to<export_values_t>();
+                        case id<global_values_t>(): {
+                                markVarGlobal(GlobalMode::Any, true);
+                                auto values = global->item.to<global_values_t>();
                                 if (values->valueList) {
                                         auto expList = x->new_ptr<ExpList_t>();
                                         for (auto name : values->nameList->names.objects()) {
-                                                addExportedVar(_parser.toString(name));
+                                                addGlobalVar(_parser.toString(name));
                                                 auto callable = x->new_ptr<Callable_t>();
                                                 callable->item.set(name);
                                                 auto chainValue = x->new_ptr<ChainValue_t>();
@@ -3842,7 +3885,7 @@ private:
                                         transformAssignment(assignment, out);
                                 } else {
                                         for (auto name : values->nameList->names.objects()) {
-                                                addExportedVar(_parser.toString(name));
+                                                addGlobalVar(_parser.toString(name));
                                         }
                                 }
                                 break;
@@ -3851,6 +3894,85 @@ private:
                 }
         }
 
+        void transformExport(Export_t* exportNode, str_list& out) {
+                auto x = exportNode;
+                if (_scopes.size() > 1) {
+                        throw std::logic_error(_info.errorMessage("Can not do module export outside root block."sv, x));
+                }
+                if (exportNode->assign) {
+                        auto expList = exportNode->target.to<ExpList_t>();
+                        if (expList->exprs.size() != exportNode->assign->values.size()) {
+                                throw std::logic_error(_info.errorMessage("Left and right expressions must be matched in export statement."sv, x));
+                        }
+                        for (auto _exp : expList->exprs.objects()) {
+                                auto exp = static_cast<Exp_t*>(_exp);
+                                if (!variableFrom(exp) &&
+                                        !exp->getByPath<Value_t, SimpleValue_t, TableLit_t>() &&
+                                        !exp->getByPath<Value_t, simple_table_t>()) {
+                                        throw std::logic_error(_info.errorMessage("Left hand expressions must be variables in export statement."sv, x));
+                                }
+                        }
+                        auto assignment = x->new_ptr<ExpListAssign_t>();
+                        assignment->expList.set(expList);
+                        assignment->action.set(exportNode->assign);
+                        transformAssignment(assignment, out);
+                        str_list names = transformAssignDefs(expList, false);
+                        auto info = extractDestructureInfo(assignment, true);
+                        if (!info.first.empty()) {
+                                for (const auto& destruct : info.first)
+                                        for (const auto& item : destruct.items)
+                                                if (item.isVariable)
+                                                        names.push_back(item.name);
+                        }
+                        if (_info.exportDefault) {
+                                out.back().append(indent() + _info.moduleName + s(" = "sv) + names.back() + nlr(exportNode));
+                        } else {
+                                str_list lefts, rights;
+                                for (const auto& name : names) {
+                                        lefts.push_back(_info.moduleName + s("[\""sv) + name + s("\"]"sv));
+                                        rights.push_back(name);
+                                }
+                                out.back().append(indent() + join(lefts,", "sv) + s(" = "sv) + join(rights, ", "sv) + nlr(exportNode));
+                        }
+                } else {
+                        if (_info.exportDefault) {
+                                auto exp = exportNode->target.to<Exp_t>();
+                                auto assignment = x->new_ptr<ExpListAssign_t>();
+                                assignment->expList.set(toAst<ExpList_t>(_info.moduleName, x));
+                                auto assign = x->new_ptr<Assign_t>();
+                                assign->values.push_back(exp);
+                                assignment->action.set(assign);
+                                transformAssignment(assignment, out);
+                        } else {
+                                str_list temp;
+                                auto expList = exportNode->target.to<ExpList_t>();
+                                auto assignment = x->new_ptr<ExpListAssign_t>();
+                                auto assignList = toAst<ExpList_t>(_info.moduleName + s("[#"sv) + _info.moduleName + s("+1]"sv), x);
+                                assignment->expList.set(assignList);
+                                for (auto exp : expList->exprs.objects()) {
+                                        if (auto classDecl = exp->getByPath<Value_t, SimpleValue_t, ClassDecl_t>()) {
+                                                if (classDecl->name && classDecl->name->item->getId() == id<Variable_t>()) {
+                                                        transformClassDecl(classDecl, temp, ExpUsage::Common);
+                                                        auto name = _parser.toString(classDecl->name->item);
+                                                        assignment->expList.set(toAst<ExpList_t>(_info.moduleName + s("[\""sv) + name + s("\"]"sv), x));
+                                                        auto assign = x->new_ptr<Assign_t>();
+                                                        assign->values.push_back(toAst<Exp_t>(name, x));
+                                                        assignment->action.set(assign);
+                                                        transformAssignment(assignment, temp);
+                                                        assignment->expList.set(assignList);
+                                                        continue;
+                                                }
+                                        }
+                                        auto assign = x->new_ptr<Assign_t>();
+                                        assign->values.push_back(exp);
+                                        assignment->action.set(assign);
+                                        transformAssignment(assignment, temp);
+                                }
+                                out.push_back(join(temp));
+                        }
+                }
+        }
+
         void transformTable(ast_node* table, const node_container& pairs, str_list& out) {
                 if (pairs.empty()) {
                         out.push_back(s("{ }"sv));
diff --git a/src/MoonP/moon_parser.cpp b/src/MoonP/moon_parser.cpp
index fecf869..baa8eff 100644
--- a/src/MoonP/moon_parser.cpp
+++ b/src/MoonP/moon_parser.cpp
@@ -28,8 +28,8 @@ std::unordered_set<std::string> Keywords = {
         "repeat", "return", "then", "true", "until",
         "while", // Lua keywords
         "as", "class", "continue", "export", "extends",
-        "from", "import", "switch", "unless", "using",
-        "when", "with" // Moon keywords
+        "from", "global", "import", "switch", "unless",
+        "using", "when", "with" // Moon keywords
 };
 
 MoonParser::MoonParser() {
@@ -74,9 +74,15 @@ MoonParser::MoonParser() {
         Variable = pl::user(Name, [](const item_t& item) {
                 State* st = reinterpret_cast<State*>(item.user_data);
                 for (auto it = item.begin; it != item.end; ++it) st->buffer += static_cast<char>(*it);
-                auto it = Keywords.find(st->buffer);
+                auto isValid = Keywords.find(st->buffer) == Keywords.end();
+                if (isValid) {
+                        if (st->buffer == st->moduleName) {
+                                st->moduleFix++;
+                                st->moduleName = std::string("_module_"sv) + std::to_string(st->moduleFix);
+                        }
+                }
                 st->buffer.clear();
-                return it == Keywords.end();
+                return isValid;
         });
 
         LuaKeyword = pl::user(Name, [](const item_t& item) {
@@ -153,7 +159,7 @@ MoonParser::MoonParser() {
                 return true;
         });
 
-        InBlock = Advance >> Block >> PopIndent;
+        InBlock = Advance >> ensure(Block, PopIndent);
 
         local_flag = expr('*') | expr('^');
         Local = key("local") >> ((Space >> local_flag) | NameList);
@@ -211,21 +217,18 @@ MoonParser::MoonParser() {
                 DisableDo >> ensure(for_in, PopDo) >>
                 -key("do") >> Body;
 
-        Do = pl::user(key("do") >> Body, [](const item_t& item)
-        {
+        Do = pl::user(key("do"), [](const item_t& item) {
                 State* st = reinterpret_cast<State*>(item.user_data);
                 return st->doStack.empty() || st->doStack.top();
-        });
+        }) >> Body;
 
-        DisableDo = pl::user(true_(), [](const item_t& item)
-        {
+        DisableDo = pl::user(true_(), [](const item_t& item) {
                 State* st = reinterpret_cast<State*>(item.user_data);
                 st->doStack.push(false);
                 return true;
         });
 
-        PopDo = pl::user(true_(), [](const item_t& item)
-        {
+        PopDo = pl::user(true_(), [](const item_t& item) {
                 State* st = reinterpret_cast<State*>(item.user_data);
                 st->doStack.pop();
                 return true;
@@ -312,11 +315,7 @@ MoonParser::MoonParser() {
 
         LuaStringContent = *(not_(LuaStringClose) >> Any);
 
-        LuaString = pl::user(LuaStringOpen >> -Break >> LuaStringContent >> LuaStringClose, [](const item_t& item) {
-                State* st = reinterpret_cast<State*>(item.user_data);
-                st->stringOpen = -1;
-                return true;
-        });
+        LuaString = LuaStringOpen >> -Break >> LuaStringContent >> LuaStringClose;
 
         Parens = sym('(') >> *SpaceBreak >> Exp >> *SpaceBreak >> sym(')');
         Callable = Space >> Variable | SelfName | VarArg | Parens;
@@ -392,9 +391,30 @@ MoonParser::MoonParser() {
                 -(key("extends")  >> PreventIndent >> ensure(Exp, PopIndent)) >>
                 -ClassBlock;
 
-        export_values = NameList >> -(sym('=') >> ExpListLow);
-        export_op = expr('*') | expr('^');
-        Export = key("export") >> (ClassDecl | (Space >> export_op) | export_values);
+        global_values = NameList >> -(sym('=') >> ExpListLow);
+        global_op = expr('*') | expr('^');
+        Global = key("global") >> (ClassDecl | (Space >> global_op) | global_values);
+
+        export_default = key("default");
+
+        Export = pl::user(key("export"), [](const item_t& item) {
+                State* st = reinterpret_cast<State*>(item.user_data);
+                st->exportCount++;
+                return true;
+        }) >> ((pl::user(export_default, [](const item_t& item) {
+                State* st = reinterpret_cast<State*>(item.user_data);
+                bool isValid = !st->exportDefault && st->exportCount == 1;
+                st->exportDefault = true;
+                return isValid;
+        }) >> Exp)
+        | (pl::user(true_(), [](const item_t& item) {
+                State* st = reinterpret_cast<State*>(item.user_data);
+                if (st->exportDefault && st->exportCount > 1) {
+                        return false;
+                } else {
+                        return true;
+                }
+        }) >> ExpList >> -Assign)) >> not_(Space >> statement_appendix);
 
         variable_pair = sym(':') >> Variable;
 
@@ -479,12 +499,12 @@ MoonParser::MoonParser() {
         statement_appendix = (if_else_line | unless_line | CompInner) >> Space;
         Statement = (
                 Import | While | For | ForEach |
-                Return | Local | Export | Space >> BreakLoop |
+                Return | Local | Global | Export | Space >> BreakLoop |
                 Backcall | ExpListAssign
         ) >> Space >>
         -statement_appendix;
 
-        Body = -Space >> Break >> *EmptyLine >> InBlock | Statement;
+        Body = Space >> Break >> *EmptyLine >> InBlock | Statement;
 
         empty_line_stop = Space >> and_(Stop);
         Line = CheckIndent >> Statement | empty_line_stop;
@@ -498,7 +518,7 @@ ParseInfo MoonParser::parse(std::string_view codes, rule& r) {
         ParseInfo res;
         try {
                 res.codes = std::make_unique<input>();
-                *(res.codes) = _converter.from_bytes(codes.begin(), codes.end());
+                *(res.codes) = _converter.from_bytes(&codes.front(), &codes.back() + 1);
         } catch (const std::range_error&) {
                 res.error = "Invalid text encoding."sv;
                 return res;
@@ -507,6 +527,10 @@ ParseInfo MoonParser::parse(std::string_view codes, rule& r) {
         try {
                 State state;
                 res.node.set(pl::parse(*(res.codes), r, errors, &state));
+                if (state.exportCount > 0) {
+                        res.moduleName = std::move(state.moduleName);
+                        res.exportDefault = state.exportDefault;
+                }
         } catch (const std::logic_error& err) {
                 res.error = err.what();
                 return res;
@@ -538,7 +562,7 @@ std::string MoonParser::toString(input::iterator begin, input::iterator end) {
 }
 
 input MoonParser::encode(std::string_view codes) {
-        return _converter.from_bytes(codes.begin(), codes.end());
+        return _converter.from_bytes(&codes.front(), &codes.back() + 1);
 }
 
 std::string MoonParser::decode(const input& codes) {
@@ -572,7 +596,6 @@ std::string ParseInfo::errorMessage(std::string_view msg, const input_range* loc
                         count++;
                 }
         }
-        auto line = Converter{}.to_bytes(std::wstring(begin, end));
         int oldCol = loc->m_begin.m_col;
         int col = std::max(0, oldCol - 1);
         auto it = begin;
@@ -582,6 +605,7 @@ std::string ParseInfo::errorMessage(std::string_view msg, const input_range* loc
                 }
                 ++it;
         }
+        auto line = Converter{}.to_bytes(std::wstring(begin, end));
         Utils::replace(line, "\t"sv, " "sv);
         std::ostringstream buf;
         buf << loc->m_begin.m_line << ": "sv << msg <<
diff --git a/src/MoonP/moon_parser.h b/src/MoonP/moon_parser.h
index 12f735b..eefcba5 100644
--- a/src/MoonP/moon_parser.h
+++ b/src/MoonP/moon_parser.h
@@ -26,6 +26,8 @@ struct ParseInfo {
         ast_ptr<false, ast_node> node;
         std::string error;
         std::unique_ptr<input> codes;
+        bool exportDefault = false;
+        std::string moduleName;
         std::string errorMessage(std::string_view msg, const input_range* loc) const;
 };
 
@@ -72,10 +74,13 @@ protected:
         struct State {
                 State() {
                         indents.push(0);
-                        stringOpen = -1;
                 }
+                bool exportDefault = false;
+                int exportCount = 0;
+                int moduleFix = 0;
+                size_t stringOpen = 0;
+                std::string moduleName = "_module_0";
                 std::string buffer;
-                size_t stringOpen;
                 std::stack<int> indents;
                 std::stack<bool> doStack;
         };
@@ -124,8 +129,8 @@ private:
         rule ImportNameList;
         rule import_literal_chain;
         rule WithExp;
-        rule PopDo;
         rule DisableDo;
+        rule PopDo;
         rule SwitchElse;
         rule SwitchBlock;
         rule IfElseIf;
@@ -181,9 +186,9 @@ private:
         AST_RULE(SelfName)
         AST_RULE(KeyName)
         AST_RULE(VarArg)
-        AST_RULE(local_flag)
         AST_RULE(Seperator)
         AST_RULE(NameList)
+        AST_RULE(local_flag)
         AST_RULE(Local)
         AST_RULE(colon_import_name)
         AST_RULE(import_literal_inner)
@@ -249,8 +254,10 @@ private:
         AST_RULE(class_member_list)
         AST_RULE(ClassBlock)
         AST_RULE(ClassDecl)
-        AST_RULE(export_values)
-        AST_RULE(export_op)
+        AST_RULE(global_values)
+        AST_RULE(global_op)
+        AST_RULE(Global)
+        AST_RULE(export_default)
         AST_RULE(Export)
         AST_RULE(variable_pair)
         AST_RULE(normal_pair)