[Feat] 详细区分左值(LvObject)与右值(RvObject -> ObjectPtr)

[Impl] 重构evaluator.cpp + hpp 全部
[Feat] 增加对于IndexExpr的解析
[Fix][Impl] 现在点运算符不由BinaryExpr负责,增加MemberExpr,单独实现解析
[Impl] 项目目录全部翻修, src/目录下单独文件夹放置每一个模块

include/Ast/AccessModifier.hpp

@@ -1,14 +0,0 @@
-#pragma once
-
-namespace Fig
-{
-    enum class AccessModifier
-    {
-        Normal,
-        Const,
-        Final,
-        Public,
-        PublicConst,
-        PublicFinal,
-    };
-};

include/ast.hpp

@@ -1,24 +0,0 @@
-#pragma once
-
-#include <Ast/astBase.hpp>
-
-#include <Ast/AccessModifier.hpp>
-#include <Ast/BinaryExpr.hpp>
-#include <Ast/ContainerInitExprs.hpp>
-#include <Ast/ControlSt.hpp>
-#include <Ast/ExpressionStmt.hpp>
-#include <Ast/ForSt.hpp>
-#include <Ast/FunctionCall.hpp>
-#include <Ast/functionParameters.hpp>
-#include <Ast/FunctionDefSt.hpp>
-#include <Ast/FunctionLiteralExpr.hpp>
-#include <Ast/IfSt.hpp>
-#include <Ast/ImplementSt.hpp>
-#include <Ast/InitExpr.hpp>
-#include <Ast/StructDefSt.hpp>
-#include <Ast/TernaryExpr.hpp>
-#include <Ast/UnaryExpr.hpp>
-#include <Ast/ValueExpr.hpp>
-#include <Ast/VarDef.hpp>
-#include <Ast/VarExpr.hpp>
-#include <Ast/WhileSt.hpp>

include/evaluator.hpp

@@ -1,130 +0,0 @@
-#pragma once
-
-#include <builtins.hpp>
-#include <error.hpp>
-#include <fig_string.hpp>
-#include <ast.hpp>
-#include <value.hpp>
-#include <context.hpp>
-#include <parser.hpp>
-
-namespace Fig
-{
-
-    template <const char *errName>
-    class EvaluatorError final : public AddressableError
-    {
-    public:
-        const char* errorName = errName;
-        virtual FString toString() const override
-        {
-            std::string msg = std::format("[Eve: {}] {} in [{}] {}", errName, std::string(this->message.begin(), this->message.end()), this->src_loc.file_name(), this->src_loc.function_name());
-            return FString(msg);
-        }
-        using AddressableError::AddressableError;
-        explicit EvaluatorError(FStringView _msg,
-                                Ast::AstAddressInfo aai,
-                                std::source_location loc = std::source_location::current()) :
-            AddressableError(_msg, aai.line, aai.column, loc)
-        {
-        }
-
-        virtual FString getErrorType() const override
-        {
-            return FString("[Eval]" + std::string(errorName));
-        }
-    };
-    struct StatementResult
-    {
-        ObjectPtr result;
-        enum class Flow
-        {
-            Normal,
-            Return,
-            Break,
-            Continue
-        } flow;
-
-        StatementResult(ObjectPtr val, Flow f = Flow::Normal) :
-            result(val), flow(f)
-        {
-        }
-
-        static StatementResult normal(ObjectPtr val = Object::getNullInstance())
-        {
-            return StatementResult(val, Flow::Normal);
-        }
-        static StatementResult returnFlow(ObjectPtr val)
-        {
-            return StatementResult(val, Flow::Return);
-        }
-        static StatementResult breakFlow()
-        {
-            return StatementResult(Object::getNullInstance(), Flow::Break);
-        }
-        static StatementResult continueFlow()
-        {
-            return StatementResult(Object::getNullInstance(), Flow::Continue);
-        }
-
-        bool isNormal() const { return flow == Flow::Normal; }
-        bool shouldReturn() const { return flow == Flow::Return; }
-        bool shouldBreak() const { return flow == Flow::Break; }
-        bool shouldContinue() const { return flow == Flow::Continue; }
-    };
-
-    class Evaluator
-    {
-    private:
-        std::vector<Ast::AstBase> asts;
-        std::shared_ptr<Context> globalContext;
-        std::shared_ptr<Context> currentContext;
-
-        Ast::AstAddressInfo currentAddressInfo;
-
-    public:
-        Evaluator(const std::vector<Ast::AstBase> &a) :
-            asts(a)
-        {
-            globalContext = std::make_shared<Context>(FString(u8"global"));
-            currentContext = globalContext;
-
-            for (auto &[name, fn] : Builtins::builtinFunctions)
-            {
-                int argc = Builtins::getBuiltinFunctionParamCount(name);
-                Function f(fn, argc);
-                globalContext->def(
-                    name,
-                    ValueType::Function,
-                    AccessModifier::PublicConst,
-                    std::make_shared<Object>(f));
-            }
-
-            for (auto &[name, val] : Builtins::builtinValues)
-            {
-                globalContext->def(
-                    name,
-                    val->getTypeInfo(),
-                    AccessModifier::PublicConst,
-                    val);
-            }
-        }
-
-        std::shared_ptr<Context> getCurrentContext() { return currentContext; }
-        std::shared_ptr<Context> getGlobalContext() { return globalContext; }
-
-        ObjectPtr __evalOp(Ast::Operator, const ObjectPtr &, const ObjectPtr & = Object::getNullInstance());
-        ObjectPtr evalBinary(const Ast::BinaryExpr &);
-        ObjectPtr evalUnary(const Ast::UnaryExpr &);
-
-        StatementResult evalBlockStatement(const Ast::BlockStatement &, ContextPtr = nullptr);
-        StatementResult evalStatement(const Ast::Statement &);
-
-        ObjectPtr evalFunctionCall(const Function &, const Ast::FunctionArguments &, FString fnName = u8"<anonymous>");
-
-        ObjectPtr eval(Ast::Expression);
-        void run();
-        void printStackTrace() const;
-    };
-
-} // namespace Fig

include/module.hpp

@@ -1,47 +0,0 @@
-#pragma once
-
-#include <memory>
-
-#include <fig_string.hpp>
-#include <value.hpp>
-#include <context.hpp>
-
-namespace Fig
-{
-    class Module
-    {
-    public:
-        const FString name;
-        const FString spec;
-        const FString path;
-        
-        std::shared_ptr<Context> context; // module-level context
-
-        /*
-        
-        import module -> automatically create a module context and call function `init` if exists
-        all global functions, variables, structs, etc will be stored in module context
-        then module context will be linked to the current context
-        
-        */
-        Module(const FString &moduleName, const FString &moduleSpec, const FString &modulePath) :
-            name(moduleName), spec(moduleSpec), path(modulePath)
-        {
-            context = std::make_shared<Context>(FString(std::format("<Module {}>", name.toBasicString())), nullptr);
-        }
-
-        bool hasSymbol(const FString &symbolName)
-        {
-            return context->contains(symbolName);
-        }
-        Value getSymbol(const FString &symbolName)
-        {
-            auto valOpt = context->get(symbolName);
-            if (!valOpt.has_value())
-            {
-                throw RuntimeError(FStringView(std::format("Symbol '{}' not found in module '{}'", symbolName.toBasicString(), name.toBasicString())));
-            }
-            return valOpt.value();
-        }
-    };
-};

src/Ast/AccessModifier.hpp

@@ -0,0 +1,23 @@
+#pragma once
+
+#include <cstdint>
+namespace Fig
+{
+    enum class AccessModifier : uint8_t
+    {
+        Normal,
+        Const,
+        Public,
+        PublicConst,
+    };
+
+    inline bool isAccessPublic(AccessModifier am)
+    {
+        return am == AccessModifier::Public || am == AccessModifier::PublicConst;
+    }
+
+    inline bool isAccessConst(AccessModifier am)
+    {
+        return am == AccessModifier::Const || am == AccessModifier::PublicConst;
+    }
+};

src/Ast/Expressions/FunctionCall.hpp

@@ -2,7 +2,7 @@
 #pragma once
 
 #include <Ast/astBase.hpp>
-#include <value.hpp>
+#include <Value/value.hpp>
 
 namespace Fig::Ast
 {
@@ -21,7 +21,7 @@ namespace Fig::Ast
     class FunctionCallExpr final : public ExpressionAst
     {
     public:
-        Expression callee; // 不是 name 了！！
+        Expression callee;
         FunctionArguments arg;
 
         FunctionCallExpr()

src/Ast/Expressions/FunctionLiteralExpr.hpp

@@ -2,7 +2,7 @@
 
 #include <Ast/astBase.hpp>
 #include <Ast/functionParameters.hpp>
-#include <fig_string.hpp>
+#include <Core/fig_string.hpp>
 #include <variant>
 
 namespace Fig::Ast

src/Ast/Expressions/PostfixExprs.hpp

@@ -0,0 +1,49 @@
+#pragma once
+
+#include <Ast/astBase.hpp>
+
+namespace Fig::Ast
+{
+    // actually, function call is postfix, too
+    // but it's too long, so use a single file (FunctionCall.hpp)
+
+    class MemberExprAst final : public ExpressionAst
+    {
+    public:
+        Expression base;
+        FString member;
+
+        MemberExprAst()
+        {
+            type = AstType::MemberExpr;
+        }
+
+        MemberExprAst(Expression _base, FString _member) :
+            base(std::move(_base)), member(std::move(_member))
+        {
+            type = AstType::MemberExpr;
+        }
+    };
+
+    using MemberExpr = std::shared_ptr<MemberExprAst>;
+
+    class IndexExprAst final : public ExpressionAst
+    {
+    public:
+        Expression base;
+        Expression index;
+
+        IndexExprAst()
+        {
+            type = AstType::IndexExpr;
+        }
+
+        IndexExprAst(Expression _base, Expression _index) :
+            base(std::move(_base)), index(std::move(_index))
+        {
+            type = AstType::IndexExpr;
+        }
+    };
+
+    using IndexExpr = std::shared_ptr<IndexExprAst>;
+}; // namespace Fig::Ast

src/Ast/Expressions/ValueExpr.hpp

@@ -2,7 +2,7 @@
 
 #include <Ast/astBase.hpp>
 
-#include <value.hpp>
+#include <Value/value.hpp>
 
 namespace Fig::Ast
 {

src/Ast/Statements/FunctionDefSt.hpp

@@ -2,9 +2,8 @@
 
 #include <Ast/astBase.hpp>
 #include <Ast/functionParameters.hpp>
-#include <fig_string.hpp>
 
-#include <value.hpp>
+#include <Value/value.hpp>
 
 namespace Fig::Ast
 {

src/Ast/Statements/StructDefSt.hpp

@@ -1,7 +1,6 @@
 #pragma once
 
 #include <Ast/astBase.hpp>
-#include <fig_string.hpp>
 #include <Ast/AccessModifier.hpp>
 
 #include <vector>

src/Ast/ast.hpp

@@ -0,0 +1,26 @@
+#pragma once
+
+#include <Ast/astBase.hpp>
+#include <Ast/AccessModifier.hpp>
+#include <Ast/functionParameters.hpp>
+
+#include <Ast/Expressions/BinaryExpr.hpp>
+#include <Ast/Expressions/ContainerInitExprs.hpp>
+#include <Ast/Expressions/FunctionCall.hpp>
+#include <Ast/Expressions/FunctionLiteralExpr.hpp>
+#include <Ast/Expressions/InitExpr.hpp>
+#include <Ast/Expressions/PostfixExprs.hpp>
+#include <Ast/Expressions/TernaryExpr.hpp>
+#include <Ast/Expressions/UnaryExpr.hpp>
+#include <Ast/Expressions/ValueExpr.hpp>
+#include <Ast/Expressions/VarExpr.hpp>
+
+#include <Ast/Statements/VarDef.hpp>
+#include <Ast/Statements/WhileSt.hpp>
+#include <Ast/Statements/StructDefSt.hpp>
+#include <Ast/Statements/IfSt.hpp>
+#include <Ast/Statements/ImplementSt.hpp>
+#include <Ast/Statements/FunctionDefSt.hpp>
+#include <Ast/Statements/ControlSt.hpp>
+#include <Ast/Statements/ExpressionStmt.hpp>
+#include <Ast/Statements/ForSt.hpp>

src/Ast/astBase.hpp

@@ -1,7 +1,7 @@
 #pragma once
 
-#include <token.hpp>
-#include <fig_string.hpp>
+#include <Token/token.hpp>
+#include <Core/fig_string.hpp>
 
 #include <format>
 #include <unordered_map>
@@ -20,15 +20,21 @@ namespace Fig::Ast
         /* Expression */
         ValueExpr,
         VarExpr,
-        FunctionCall,
         LambdaExpr,
         UnaryExpr,
         BinaryExpr,
         TernaryExpr,
-        ListExpr, // []
-        TupleExpr, // ()
-        MapExpr,   // {}
-        InitExpr, // struct{}
+
+        /* Postfix */
+        MemberExpr, // a.b
+        IndexExpr,  // a[b]
+        FunctionCall, // a()
+
+        /* Literals */
+        ListExpr,  // [1, "2", 3
+        TupleExpr, // (1, 2, 3)
+        MapExpr,   // {a: 1}
+        InitExpr,  // struct{"123", 456}
         FunctionLiteralExpr,
 
         /* Statement */
@@ -112,8 +118,7 @@ namespace Fig::Ast
         virtual FString typeName()
         {
             return FString::fromStringView(
-                FStringView::fromBasicStringView(magic_enum::enum_name(type))
-            );
+                FStringView::fromBasicStringView(magic_enum::enum_name(type)));
         }
         virtual FString toString()
         {
@@ -216,9 +221,6 @@ namespace Fig::Ast
         // 赋值表达式
         Assign, // =
         // Walrus, // :=
-
-        // 点运算符 .
-        Dot,
     };
 
     static const std::unordered_set<Operator> unaryOps{
@@ -251,7 +253,8 @@ namespace Fig::Ast
         Operator::ShiftRight,
 
         // Operator::Walrus,
-        Operator::Dot};
+        // Operator::Dot
+    };
     static const std::unordered_set<Operator> ternaryOps{Operator::TernaryCond};
 
     static const std::unordered_map<TokenType, Operator> TokenToOp{
@@ -292,8 +295,6 @@ namespace Fig::Ast
         // 赋值表达式
         {TokenType::Assign, Operator::Assign},
         // {TokenType::Walrus, Operator::Walrus},
-        // 点运算符
-        {TokenType::Dot, Operator::Dot},
     }; // :=
 
     inline bool isOpUnary(Operator op)

src/Ast/functionParameters.hpp

@@ -2,7 +2,7 @@
 
 #include <Ast/astBase.hpp>
 #include <Value/Type.hpp>
-#include <fig_string.hpp>
+#include <Core/fig_string.hpp>
 
 namespace Fig::Ast
 {

src/Context/context.hpp

@@ -4,32 +4,31 @@
 #include <iostream>
 #include <memory>
 
-#include <context_forward.hpp>
-#include <fig_string.hpp>
-#include <value.hpp>
+#include <Context/context_forward.hpp>
+#include <Core/fig_string.hpp>
+#include <Value/value.hpp>
 
 namespace Fig
 {
+
     class Context : public std::enable_shared_from_this<Context>
     {
     private:
         FString scopeName;
-        std::unordered_map<FString, TypeInfo> varTypes;
-        std::unordered_map<FString, ObjectPtr> variables;
-        std::unordered_map<FString, AccessModifier> ams;
+        std::unordered_map<FString, std::shared_ptr<VariableSlot>> variables;
 
         std::unordered_map<std::size_t, Function> functions;
         std::unordered_map<std::size_t, FString> functionNames;
-
         std::unordered_map<std::size_t, FString> structTypeNames;
+
     public:
         ContextPtr parent;
 
         Context(const Context &) = default;
         Context(const FString &name, ContextPtr p = nullptr) :
             scopeName(name), parent(p) {}
-        Context(const FString &name, std::unordered_map<FString, TypeInfo> types, std::unordered_map<FString, ObjectPtr> vars, std::unordered_map<FString, AccessModifier> _ams) :
-            scopeName(std::move(name)), varTypes(std::move(types)), variables(std::move(vars)), ams(std::move(_ams)) {}
+        Context(const FString &name, std::unordered_map<FString, TypeInfo> types, std::unordered_map<FString, std::shared_ptr<VariableSlot>> vars, std::unordered_map<FString, AccessModifier> _ams) :
+            scopeName(std::move(name)), variables(std::move(vars)) {}
 
         void setParent(ContextPtr _parent)
         {
@@ -46,11 +45,9 @@ namespace Fig
             return scopeName;
         }
 
-        void merge(const Context& c)
+        void merge(const Context &c)
         {
-            varTypes.insert(c.varTypes.begin(), c.varTypes.end());
             variables.insert(c.variables.begin(), c.variables.end());
-            ams.insert(c.ams.begin(), c.ams.end());
             functions.insert(c.functions.begin(), c.functions.end());
             functionNames.insert(c.functionNames.begin(), c.functionNames.end());
             structTypeNames.insert(c.structTypeNames.begin(), c.structTypeNames.end());
@@ -61,20 +58,20 @@ namespace Fig
             return functions;
         }
 
-        std::optional<ObjectPtr> get(const FString &name)
+        std::shared_ptr<VariableSlot> get(const FString &name)
         {
             auto it = variables.find(name);
             if (it != variables.end())
                 return it->second;
             if (parent)
                 return parent->get(name);
-            return std::nullopt;
+            throw RuntimeError(FStringView(std::format("Variable '{}' not defined", name.toBasicString())));
         }
         AccessModifier getAccessModifier(const FString &name)
         {
             if (variables.contains(name))
             {
-                return ams[name];
+                return variables[name]->am;
             }
             else if (parent != nullptr)
             {
@@ -85,33 +82,17 @@ namespace Fig
                 throw RuntimeError(FStringView(std::format("Variable '{}' not defined", name.toBasicString())));
             }
         }
-        ContextPtr createCopyWithPublicVariables()
-        {
-            std::unordered_map<FString, TypeInfo> _varTypes;
-            std::unordered_map<FString, ObjectPtr> _variables;
-            std::unordered_map<FString, AccessModifier> _ams;
-            for (const auto &p : this->variables)
-            {
-                if (isVariablePublic(p.first))
-                {
-                    _variables[p.first] = std::make_shared<Object>(*p.second); // copy 
-                    _varTypes[p.first] = varTypes[p.first];
-                    _ams[p.first] = ams[p.first];
-                }
-            }
-            return std::make_shared<Context>(this->scopeName, _varTypes, _variables, _ams);
-        }
         bool isVariableMutable(const FString &name)
         {
             AccessModifier am = getAccessModifier(name); // may throw
-            return am == AccessModifier::Normal or am == AccessModifier::Public;
+            return !isAccessConst(am);
         }
         bool isVariablePublic(const FString &name)
         {
             AccessModifier am = getAccessModifier(name); // may throw
-            return am == AccessModifier::Public or am == AccessModifier::PublicConst or am == AccessModifier::PublicFinal;
+            return isAccessPublic(am);
         }
-        void set(const FString &name, const Object &value)
+        void set(const FString &name, ObjectPtr value)
         {
             if (variables.contains(name))
             {
@@ -119,7 +100,7 @@ namespace Fig
                 {
                     throw RuntimeError(FStringView(std::format("Variable '{}' is immutable", name.toBasicString())));
                 }
-                variables[name] = std::make_shared<Object>(value);
+                variables[name]->value = value;
             }
             else if (parent != nullptr)
             {
@@ -130,11 +111,11 @@ namespace Fig
                 throw RuntimeError(FStringView(std::format("Variable '{}' not defined", name.toBasicString())));
             }
         }
-        void _update(const FString &name, const Object &value)
+        void _update(const FString &name, ObjectPtr value)
         {
             if (variables.contains(name))
             {
-                variables[name] = std::make_shared<Object>(value);
+                variables[name]->value = value;
             }
             else if (parent != nullptr)
             {
@@ -151,10 +132,11 @@ namespace Fig
             {
                 throw RuntimeError(FStringView(std::format("Variable '{}' already defined in this scope", name.toBasicString())));
             }
-            variables[name] = std::make_shared<Object>(*value);
-            varTypes[name] = ti;
-            ams[name] = am;
-
+            variables[name] = std::make_shared<VariableSlot>(
+                name,
+                value,
+                ti,
+                am);
             if (ti == ValueType::Function and value->getTypeInfo() == ValueType::Function)
             {
                 auto &fn = value->as<Function>();
@@ -234,15 +216,7 @@ namespace Fig
 
         TypeInfo getTypeInfo(const FString &name)
         {
-            if (varTypes.contains(name))
-            {
-                return varTypes[name];
-            }
-            else if (parent != nullptr)
-            {
-                return parent->getTypeInfo(name);
-            }
-            throw RuntimeError(FStringView(std::format("Variable '{}' not defined", name.toBasicString())));
+            return get(name)->declaredType;
         }
         bool isInFunctionContext()
         {
@@ -262,8 +236,7 @@ namespace Fig
             ContextPtr ctx = shared_from_this();
             while (ctx)
             {
-                if (ctx->getScopeName().find(u8"<While ") == 0 or
-                    ctx->getScopeName().find(u8"<For ") == 0)
+                if (ctx->getScopeName().find(u8"<While ") == 0 or ctx->getScopeName().find(u8"<For ") == 0)
                 {
                     return true;
                 }

src/Core/core.hpp

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <fig_string.hpp>
+#include <Core/fig_string.hpp>
 #include <cstdint>
 #include <string_view>
 

src/Core/warning.cpp

@@ -1,4 +1,4 @@
-#include <warning.hpp>
+#include <Core/warning.hpp>
 
 namespace Fig
 {

src/Core/warning.hpp

@@ -1,8 +1,8 @@
 #pragma once
 
-#include <fig_string.hpp>
+#include <Core/fig_string.hpp>
 
-#include <magic_enum/magic_enum.hpp>
+#include <Utils/magic_enum/magic_enum.hpp>
 #include <unordered_map>
 
 namespace Fig

src/Error/error.hpp

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <fig_string.hpp>
+#include <Core/fig_string.hpp>
 
 #include <exception>
 #include <format>

src/Error/errorLog.hpp

@@ -1,7 +1,7 @@
 #pragma once
 
-#include <error.hpp>
-#include <core.hpp>
+#include <Error/error.hpp>
+#include <Core/core.hpp>
 
 #include <print>
 #include <vector>

src/Evaluator/evaluator.hpp

@@ -0,0 +1,116 @@
+#include <Ast/ast.hpp>
+
+#include <Context/context.hpp>
+#include <Error/error.hpp>
+#include <Module/builtins.hpp>
+
+
+namespace Fig
+{
+    struct StatementResult
+    {
+        ObjectPtr result;
+        enum class Flow
+        {
+            Normal,
+            Return,
+            Break,
+            Continue
+        } flow;
+
+        StatementResult(ObjectPtr val, Flow f = Flow::Normal) :
+            result(val), flow(f)
+        {
+        }
+
+        static StatementResult normal(ObjectPtr val = Object::getNullInstance())
+        {
+            return StatementResult(val, Flow::Normal);
+        }
+        static StatementResult returnFlow(ObjectPtr val)
+        {
+            return StatementResult(val, Flow::Return);
+        }
+        static StatementResult breakFlow()
+        {
+            return StatementResult(Object::getNullInstance(), Flow::Break);
+        }
+        static StatementResult continueFlow()
+        {
+            return StatementResult(Object::getNullInstance(), Flow::Continue);
+        }
+
+        bool isNormal() const { return flow == Flow::Normal; }
+        bool shouldReturn() const { return flow == Flow::Return; }
+        bool shouldBreak() const { return flow == Flow::Break; }
+        bool shouldContinue() const { return flow == Flow::Continue; }
+    };
+
+    class Evaluator
+    {
+    private:
+        ContextPtr global;
+    public:
+
+        void SetGlobalContext(ContextPtr ctx)
+        {
+            assert(ctx != nullptr);
+            global = ctx;
+        }
+
+        void CreateGlobalContext()
+        {
+            global = std::make_shared<Context>(
+                FString(u8"<Global>"));
+        }
+
+        void RegisterBuiltins()
+        {
+            assert(global != nullptr);
+
+            for (auto &[name, fn] : Builtins::builtinFunctions)
+            {
+                int argc = Builtins::getBuiltinFunctionParamCount(name);
+                Function f(fn, argc);
+                global->def(
+                    name,
+                    ValueType::Function,
+                    AccessModifier::Const,
+                    std::make_shared<Object>(f)
+                );
+            }
+
+            for (auto &[name, val] : Builtins::builtinValues)
+            {
+                global->def(
+                    name,
+                    val->getTypeInfo(),
+                    AccessModifier::Const,
+                    val
+                );
+            }
+        }
+        /* Left-value eval*/
+        LvObject evalVarExpr(Ast::VarExpr, ContextPtr);
+        LvObject evalMemberExpr(Ast::MemberExpr, ContextPtr); // a.b
+        LvObject evalIndexExpr(Ast::IndexExpr, ContextPtr); // a[b]
+
+        LvObject evalLv(Ast::Expression, ContextPtr); // for access: a.b / index a[b]
+
+        /* Right-value eval*/
+        
+        RvObject evalBinary(Ast::BinaryExpr, ContextPtr); // normal binary expr: +, -, *....
+        RvObject evalUnary(Ast::UnaryExpr, ContextPtr); // unary expr
+        RvObject evalTernary(Ast::TernaryExpr, ContextPtr); // ternary expr
+
+        RvObject evalFunctionCall(const Function&, const Ast::FunctionArguments&, const FString& ,ContextPtr);    // function call
+        RvObject eval(Ast::Expression, ContextPtr);
+        
+        StatementResult evalBlockStatement(Ast::BlockStatement, ContextPtr); // block
+        StatementResult evalStatement(Ast::Statement, ContextPtr);  // statement
+
+        StatementResult Run(std::vector<Ast::AstBase>); // Entry
+        
+        void printStackTrace();
+    };
+}; // namespace Fig

src/Evaluator/evaluator_error.hpp

@@ -0,0 +1,42 @@
+#pragma once
+
+#include <Error/error.hpp>
+#include <Ast/astBase.hpp>
+
+namespace Fig
+{
+    class EvaluatorError final : public AddressableError
+    {
+    public:
+        FString typeName;
+        using AddressableError::AddressableError;
+        EvaluatorError(FString _typeName, FString msg, Ast::AstBase ast, std::source_location loc = std::source_location::current())
+        {
+            message = FStringView::fromBasicStringView(msg.toBasicString());
+            line = ast->getAAI().line;
+            column = ast->getAAI().column;
+
+            src_loc = std::move(loc);
+
+            typeName = std::move(_typeName);
+
+        }
+        EvaluatorError(FString _typeName, std::string_view msg, Ast::AstBase ast, std::source_location loc = std::source_location::current())
+        {
+            message = FStringView::fromBasicStringView(msg);
+            line = ast->getAAI().line;
+            column = ast->getAAI().column;
+
+            src_loc = std::move(loc);
+
+            typeName = std::move(_typeName);
+        }
+
+        virtual FString getErrorType() const override
+        {
+            return typeName;
+        }
+
+
+    };
+};

src/Lexer/lexer.cpp

@@ -1,10 +1,10 @@
-#include <fig_string.hpp>
-#include <error.hpp>
-#include <token.hpp>
-#include <lexer.hpp>
+#include <Core/fig_string.hpp>
+#include <Error/error.hpp>
+#include <Token/token.hpp>
+#include <Lexer/lexer.hpp>
 
-#include <fig_string.hpp>
-#include <utils.hpp>
+#include <Core/fig_string.hpp>
+#include <Utils/utils.hpp>
 
 namespace Fig
 {
@@ -66,7 +66,7 @@ namespace Fig
         {FString(u8"func"), TokenType::Function},
         {FString(u8"var"), TokenType::Variable},
         {FString(u8"const"), TokenType::Const},
-        {FString(u8"final"), TokenType::Final},
+        // {FString(u8"final"), TokenType::Final},
         {FString(u8"while"), TokenType::While},
         {FString(u8"for"), TokenType::For},
         {FString(u8"if"), TokenType::If},

src/Lexer/lexer.hpp

@@ -6,11 +6,11 @@
 #include <unordered_map>
 #include <vector>
 
-#include <token.hpp>
-#include <error.hpp>
-#include <fig_string.hpp>
-#include <utf8_iterator.hpp>
-#include <warning.hpp>
+#include <Token/token.hpp>
+#include <Error/error.hpp>
+#include <Core/fig_string.hpp>
+#include <Core/utf8_iterator.hpp>
+#include <Core/warning.hpp>
 
 namespace Fig
 {

src/Module/builtins.hpp

@@ -1,7 +1,7 @@
 #pragma once
 
-#include <fig_string.hpp>
-#include <value.hpp>
+#include <Core/fig_string.hpp>
+#include <Value/value.hpp>
 
 #include <unordered_map>
 #include <functional>

src/Module/module.hpp

@@ -0,0 +1,47 @@
+#pragma once
+
+#include <memory>
+
+#include <Core/fig_string.hpp>
+#include <Value/value.hpp>
+#include <Context/context.hpp>
+
+namespace Fig
+{
+    // class Module
+    // {
+    // public:
+    //     const FString name;
+    //     const FString spec;
+    //     const FString path;
+        
+    //     std::shared_ptr<Context> context; // module-level context
+
+    //     /*
+        
+    //     import module -> automatically create a module context and call function `init` if exists
+    //     all global functions, variables, structs, etc will be stored in module context
+    //     then module context will be linked to the current context
+        
+    //     */
+    //     Module(const FString &moduleName, const FString &moduleSpec, const FString &modulePath) :
+    //         name(moduleName), spec(moduleSpec), path(modulePath)
+    //     {
+    //         context = std::make_shared<Context>(FString(std::format("<Module {}>", name.toBasicString())), nullptr);
+    //     }
+
+    //     bool hasSymbol(const FString &symbolName)
+    //     {
+    //         return context->contains(symbolName);
+    //     }
+    //     Object getSymbol(const FString &symbolName)
+    //     {
+    //         auto valOpt = context->get(symbolName);
+    //         if (!valOpt.has_value())
+    //         {
+    //             throw RuntimeError(FStringView(std::format("Symbol '{}' not found in module '{}'", symbolName.toBasicString(), name.toBasicString())));
+    //         }
+    //         return valOpt.value();
+    //     }
+    // };
+};

src/Parser/parser.cpp

@@ -1,4 +1,4 @@
-#include <parser.hpp>
+#include <Parser/parser.hpp>
 
 namespace Fig
 {
@@ -39,8 +39,8 @@ namespace Fig
         // 海象运算符
         // {Ast::Operator::Walrus, {2, 1}}, // 右结合
 
-        // 点运算符
-        {Ast::Operator::Dot, {40, 41}},
+        // // 点运算符
+        // {Ast::Operator::Dot, {40, 41}},
     };
 
     Ast::VarDef Parser::__parseVarDef(bool isPublic)
@@ -244,13 +244,6 @@ namespace Fig
                 next();
                 am = (isPublic ? AccessModifier::Public : AccessModifier::Normal);
             }
-            else if (isThis(TokenType::Final))
-            {
-                next();
-                expect(TokenType::Identifier, u8"field name");
-                fieldName = currentToken().getValue();
-                am = (isPublic ? AccessModifier::PublicFinal : AccessModifier::Final);
-            }
             else if (isThis(TokenType::Const))
             {
                 next();
@@ -297,7 +290,7 @@ namespace Fig
             }
             else if (isThis(TokenType::Public))
             {
-                if (isNext(TokenType::Const) or isNext(TokenType::Final))
+                if (isNext(TokenType::Const))
                 {
                     next();
                     fields.push_back(__parseStructField(true));
@@ -334,7 +327,7 @@ namespace Fig
                 next(); // consume `struct`
                 stmts.push_back(__parseStructDef(false));
             }
-            else if (isThis(TokenType::Const) or isThis(TokenType::Final))
+            else if (isThis(TokenType::Const))
             {
                 fields.push_back(__parseStructField(false));
             }
@@ -865,12 +858,40 @@ namespace Fig
             tok = currentToken();
             if (tok.getType() == TokenType::Semicolon || tok == EOFTok) break;
 
+            /* Postfix */
+
             if (tok.getType() == TokenType::LeftParen)
             {
                 lhs = __parseCall(lhs);
                 continue;
             }
 
+            // member access: a.b
+            if (tok.getType() == TokenType::Dot)
+            {
+                next(); // consume '.'
+                Token idTok = currentToken();
+                if (!idTok.isIdentifier())
+                    throwAddressableError<SyntaxError>(FStringView(u8"Expected identifier after '.'"));
+
+                FString member = idTok.getValue();
+                next(); // consume identifier
+
+                lhs = makeAst<Ast::MemberExprAst>(lhs, member);
+                continue;
+            }
+            // index: x[expr]
+            if (tok.getType() == TokenType::LeftBracket)
+            {
+                next(); // consume '['
+                auto indexExpr = parseExpression(0, TokenType::RightBracket);
+                expect(TokenType::RightBracket);
+                next(); // consume ']'
+
+                lhs = makeAst<Ast::IndexExprAst>(lhs, indexExpr);
+                continue;
+            }
+
             // ternary
             if (tok.getType() == TokenType::Question)
             {

src/Parser/parser.hpp

@@ -1,9 +1,9 @@
 #pragma once
 
-#include <ast.hpp>
-#include <lexer.hpp>
-#include <fig_string.hpp>
-#include <error.hpp>
+#include <Ast/ast.hpp>
+#include <Lexer/lexer.hpp>
+#include <Core/fig_string.hpp>
+#include <Error/error.hpp>
 
 #include <print>
 #include <unordered_map>

src/Token/token.hpp

@@ -2,9 +2,9 @@
 
 #include <cstdint>
 #include <format>
-#include <magic_enum/magic_enum.hpp>
+#include <Utils/magic_enum/magic_enum.hpp>
 
-#include <fig_string.hpp>
+#include <Core/fig_string.hpp>
 
 namespace Fig
 {
@@ -25,7 +25,7 @@ namespace Fig
         Function,  // func
         Variable,  // var
         Const,     // const
-        Final,     // final
+        // Final,     // final
         While,     // while
         For,       // for
         If,        // if

src/Utils/AstPrinter.hpp

@@ -2,8 +2,8 @@
 #include <iostream>
 #include <memory>
 #include <string>
-#include <ast.hpp>
-#include <magic_enum/magic_enum.hpp>
+#include <Ast/ast.hpp>
+#include <Utils/magic_enum/magic_enum.hpp>
 
 using namespace Fig;
 using namespace Fig::Ast;

src/Utils/utils.hpp

@@ -1,6 +1,6 @@
 #pragma once
 #pragma once
-#include <fig_string.hpp>
+#include <Core/fig_string.hpp>
 #include <string>
 #include <locale>
 #include <cwctype>

src/Value/Type.hpp

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <fig_string.hpp>
+#include <Core/fig_string.hpp>
 
 #include <variant>
 #include <map>

src/Value/containers.hpp

@@ -0,0 +1,6 @@
+#pragma once
+
+namespace Fig
+{
+    
+};

src/Value/function.hpp

@@ -1,7 +1,7 @@
 #pragma once
 
 #include <Ast/functionParameters.hpp>
-#include <context_forward.hpp>
+#include <Context/context_forward.hpp>
 
 #include <atomic>
 #include <functional>

src/Value/structInstance.hpp

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <context_forward.hpp>
+#include <Context/context_forward.hpp>
 
 namespace Fig
 {

src/Value/structType.hpp

@@ -1,11 +1,11 @@
 #pragma once
 
-#include <fig_string.hpp>
-#include <Ast/StructDefSt.hpp>
+#include <Core/fig_string.hpp>
+#include <Ast/Statements/StructDefSt.hpp>
 
 #include <Value/Type.hpp>
 
-#include <context_forward.hpp>
+#include <Context/context_forward.hpp>
 #include <atomic>
 #include <vector>
 
@@ -23,16 +23,13 @@ namespace Fig
 
         bool isPublic() const
         {
-            return am == AccessModifier::Public || am == AccessModifier::PublicConst || am == AccessModifier::PublicFinal;
+            return am == AccessModifier::Public || am == AccessModifier::PublicConst;
         }
         bool isConst() const
         {
             return am == AccessModifier::Const || am == AccessModifier::PublicConst;
         }
-        bool isFinal() const
-        {
-            return am == AccessModifier::Final || am == AccessModifier::PublicFinal;
-        }
+
     };
 
     struct StructType

src/Value/value.cpp

@@ -1,4 +1,5 @@
-#include <value.hpp>
+#include <Value/value.hpp>
+#include <Context/context.hpp>
 
 // #include <iostream>
 

src/Value/value.hpp

@@ -19,8 +19,11 @@ namespace Fig
 
     inline bool isNumberExceededIntLimit(ValueType::DoubleClass d)
     {
-        static constexpr ValueType::DoubleClass intMaxAsDouble = static_cast<ValueType::DoubleClass>(std::numeric_limits<ValueType::IntClass>::max());
-        static constexpr ValueType::DoubleClass intMinAsDouble = static_cast<ValueType::DoubleClass>(std::numeric_limits<ValueType::IntClass>::min());
+        static constexpr auto intMaxAsDouble =
+            static_cast<ValueType::DoubleClass>(std::numeric_limits<ValueType::IntClass>::max());
+
+        static constexpr auto intMinAsDouble =
+            static_cast<ValueType::DoubleClass>(std::numeric_limits<ValueType::IntClass>::min());
         return d > intMaxAsDouble || d < intMinAsDouble;
     }
 
@@ -45,13 +48,9 @@ namespace Fig
             data(n) {}
         Object(const ValueType::IntClass &i) :
             data(i) {}
-        Object(const ValueType::DoubleClass &d)
+        explicit Object(const ValueType::DoubleClass &d) :
+            data(d)
         {
-            ValueType::IntClass casted = static_cast<ValueType::IntClass>(d);
-            if (casted == d)
-                data = casted;
-            else
-                data = d;
         }
         Object(const ValueType::StringClass &s) :
             data(s) {}
@@ -392,5 +391,63 @@ namespace Fig
     };
 
     using ObjectPtr = std::shared_ptr<Object>;
+    using RvObject = ObjectPtr;
+
+    struct VariableSlot
+    {
+        FString name;
+        ObjectPtr value;
+        TypeInfo declaredType;
+        AccessModifier am;
+
+        bool isRef = false;
+        std::shared_ptr<VariableSlot> refTarget;
+    };
+
+    struct LvObject
+    {
+        std::shared_ptr<VariableSlot> slot;
+
+        const ObjectPtr& get() const
+        {
+            auto s = resolve(slot);
+            return s->value;
+        }
+
+        void set(const ObjectPtr& v)
+        {
+            auto s = resolve(slot);
+            if (s->declaredType != ValueType::Any && s->declaredType != v->getTypeInfo())
+            {
+                throw RuntimeError(
+                    FStringView(
+                        std::format("Variable `{}` expects type `{}`, but got '{}'",
+                            s->name.toBasicString(),
+                            s->declaredType.toString().toBasicString(),
+                            v->getTypeInfo().toString().toBasicString())
+                    )
+                );
+            }
+            if (isAccessConst(s->am))
+            {
+                throw RuntimeError(FStringView(
+                    std::format("Variable `{}` is immutable", s->name.toBasicString())
+                ));
+            }
+            s->value = v;
+        }
+
+        FString name() const { return resolve(slot)->name; }
+        TypeInfo declaredType() const { return resolve(slot)->declaredType; }
+        AccessModifier access() const { return resolve(slot)->am; }
+
+    private:
+        std::shared_ptr<VariableSlot> resolve(std::shared_ptr<VariableSlot> s) const
+        {
+            while (s->isRef) s = s->refTarget;
+            return s;
+        }
+    };
+
 
 } // namespace Fig

src/Value/valueError.hpp

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <error.hpp>
+#include <Error/error.hpp>
 
 namespace Fig
 {

src/evaluator.cpp

@@ -1,854 +0,0 @@
-#include <evaluator.hpp>
-#include <builtins.hpp>
-#include <utils.hpp>
-
-namespace Fig
-{
-    ObjectPtr Evaluator::__evalOp(Ast::Operator op, const ObjectPtr &lhs, const ObjectPtr &rhs)
-    {
-        using Fig::Ast::Operator;
-        switch (op)
-        {
-            case Operator::Add: return std::make_shared<Object>(*lhs + *rhs);
-            case Operator::Subtract: return std::make_shared<Object>(*lhs - *rhs);
-            case Operator::Multiply: return std::make_shared<Object>((*lhs) * (*rhs));
-            case Operator::Divide: return std::make_shared<Object>(*lhs / *rhs);
-            case Operator::Modulo: return std::make_shared<Object>(*lhs % *rhs);
-            case Operator::Power: return std::make_shared<Object>(power(*lhs, *rhs));
-
-            case Operator::And: return std::make_shared<Object>(*lhs && *rhs);
-            case Operator::Or: return std::make_shared<Object>(*lhs || *rhs);
-            case Operator::Not: return std::make_shared<Object>(!*lhs);
-
-            case Operator::Equal: return std::make_shared<Object>(*lhs == *rhs);
-            case Operator::NotEqual: return std::make_shared<Object>(*lhs != *rhs);
-            case Operator::Less: return std::make_shared<Object>(*lhs < *rhs);
-            case Operator::LessEqual: return std::make_shared<Object>(*lhs <= *rhs);
-            case Operator::Greater: return std::make_shared<Object>(*lhs > *rhs);
-            case Operator::GreaterEqual: return std::make_shared<Object>(*lhs >= *rhs);
-
-            case Operator::BitAnd: return std::make_shared<Object>(bit_and(*lhs, *rhs));
-            case Operator::BitOr: return std::make_shared<Object>(bit_or(*lhs, *rhs));
-            case Operator::BitXor: return std::make_shared<Object>(bit_xor(*lhs, *rhs));
-            case Operator::BitNot: return std::make_shared<Object>(bit_not(*lhs));
-            case Operator::ShiftLeft: return std::make_shared<Object>(shift_left(*lhs, *rhs));
-            case Operator::ShiftRight: return std::make_shared<Object>(shift_right(*lhs, *rhs));
-
-            case Operator::Assign: {
-                *lhs = *rhs;
-                return Object::getNullInstance();
-            }
-
-            // case Operator::Walrus: {
-            //     static constexpr char WalrusErrorName[] = "WalrusError";
-            //     throw EvaluatorError<WalrusErrorName>(FStringView(u8"Walrus operator is not supported"), currentAddressInfo); // using parent address info for now
-            // }
-            default:
-                throw RuntimeError(FStringView(u8"Unsupported operator"));
-        }
-    }
-
-    ObjectPtr Evaluator::evalBinary(const Ast::BinaryExpr &binExp)
-    {
-        if (binExp->op == Ast::Operator::Dot)
-        {
-            const ObjectPtr &lhs = eval(binExp->lexp);
-            if (!lhs->is<StructInstance>())
-            {
-                static constexpr char AccessOpObjectNotStructError[] = "AccessOpObjectNotStructError";
-                throw EvaluatorError<AccessOpObjectNotStructError>(FStringView(
-                                                                       std::format("Object not a struct")),
-                                                                   binExp->lexp->getAAI());
-            }
-            const StructInstance &st = lhs->as<StructInstance>();
-            Ast::VarExpr varExp;
-            Ast::FunctionCall fnCall;
-            if ((varExp = std::dynamic_pointer_cast<Ast::VarExprAst>(binExp->rexp)))
-            {
-                FString member = varExp->name;
-                auto structTypeNameOpt = currentContext->getStructName(st.parentId);
-                if (!structTypeNameOpt) throw RuntimeError(FStringView("Can't get struct type name"));
-                FString structTypeName = *structTypeNameOpt;
-                if (!st.localContext->containsInThisScope(member))
-                {
-                    static constexpr char NoAttributeError[] = "NoAttributeError";
-                    throw EvaluatorError<NoAttributeError>(FStringView(
-                                                               std::format("Struct `{}` has no attribute '{}'", structTypeName.toBasicString(), member.toBasicString())),
-                                                           binExp->rexp->getAAI());
-                }
-                if (!st.localContext->isVariablePublic(member))
-                {
-                    static constexpr char AttributeIsPrivateError[] = "AttributeIsPrivateError";
-                    throw EvaluatorError<AttributeIsPrivateError>(FStringView(
-                                                                      std::format("Attribute '{}' of class `{}` is private",
-                                                                                  structTypeName.toBasicString(),
-                                                                                  member.toBasicString())),
-                                                                  binExp->rexp->getAAI());
-                }
-                return *st.localContext->get(member); // safe
-            }
-            else if ((fnCall = std::dynamic_pointer_cast<Ast::FunctionCallExpr>(binExp->rexp)))
-            {
-                auto structTypeNameOpt = currentContext->getStructName(st.parentId);
-                if (!structTypeNameOpt) throw RuntimeError(FStringView("Can't get struct type name"));
-                FString structTypeName = *structTypeNameOpt;
-
-                FString fnName = u8"<anonymous>";
-                if (auto var = std::dynamic_pointer_cast<Ast::VarExprAst>(fnCall->callee))
-                    fnName = var->name; // function in struct has its name, so we can get the name
-                if (!st.localContext->containsInThisScope(fnName))
-                {
-                    static constexpr char NoAttributeError[] = "NoAttributeError";
-                    throw EvaluatorError<NoAttributeError>(FStringView(
-                                                               std::format("Struct `{}` has no attribute '{}'", structTypeName.toBasicString(), fnName.toBasicString())),
-                                                           binExp->rexp->getAAI());
-                }
-                if (!st.localContext->isVariablePublic(fnName))
-                {
-                    static constexpr char AttributeIsPrivateError[] = "AttributeIsPrivateError";
-                    throw EvaluatorError<AttributeIsPrivateError>(FStringView(
-                                                                      std::format("Attribute '{}' of class `{}` is private",
-                                                                                  structTypeName.toBasicString(),
-                                                                                  fnName.toBasicString())),
-                                                                  binExp->rexp->getAAI());
-                }
-                auto calleeValOpt = st.localContext->get(fnName);
-                ObjectPtr calleeVal = *calleeValOpt;
-
-                if (!calleeVal->is<Function>())
-                {
-                    static constexpr char NotAFunctionErrorName[] = "NotAFunctionError";
-                    throw EvaluatorError<NotAFunctionErrorName>(
-                        FStringView(std::format(
-                            "'{}' is not a function or callable",
-                            calleeVal->toString().toBasicString())),
-                        currentAddressInfo);
-                }
-
-                Function fn = calleeVal->as<Function>();
-
-                return evalFunctionCall(fn, fnCall->arg, fnName);
-            }
-            else
-            {
-                static constexpr char AccessOpNotAFieldNameError[] = "AccessOpNotAFieldNameError";
-                throw EvaluatorError<AccessOpNotAFieldNameError>(FStringView(
-                                                                     std::format("{} is not a field", binExp->rexp->toString().toBasicString())),
-                                                                 binExp->rexp->getAAI());
-            }
-        }
-        return __evalOp(binExp->op, eval(binExp->lexp), eval(binExp->rexp));
-    }
-    ObjectPtr Evaluator::evalUnary(const Ast::UnaryExpr &unExp)
-    {
-        using Fig::Ast::Operator;
-        switch (unExp->op)
-        {
-            case Operator::Not:
-                return std::make_shared<Object>(!*eval(unExp->exp));
-            case Operator::Subtract:
-                return std::make_shared<Object>(-*eval(unExp->exp));
-            case Operator::BitNot:
-                return std::make_shared<Object>(bit_not(*eval(unExp->exp)));
-            default:
-                throw RuntimeError(FStringView(std::format("Unsupported unary operator: {}", magic_enum::enum_name(unExp->op))));
-        }
-    }
-
-    ObjectPtr Evaluator::evalFunctionCall(const Function &fn, const Ast::FunctionArguments &fnArgs, FString fnName)
-    {
-        const Function &fnStruct = fn;
-        Ast::FunctionCallArgs evaluatedArgs;
-        if (fnStruct.isBuiltin)
-        {
-            for (const auto &argExpr : fnArgs.argv)
-            {
-                evaluatedArgs.argv.push_back(eval(argExpr));
-            }
-            if (fnStruct.builtinParamCount != -1 && fnStruct.builtinParamCount != evaluatedArgs.getLength())
-            {
-                static constexpr char BuiltinArgumentMismatchErrorName[] = "BuiltinArgumentMismatchError";
-                throw EvaluatorError<BuiltinArgumentMismatchErrorName>(FStringView(std::format("Builtin function '{}' expects {} arguments, but {} were provided", fnName.toBasicString(), fnStruct.builtinParamCount, evaluatedArgs.getLength())), currentAddressInfo);
-            }
-            return fnStruct.builtin(evaluatedArgs.argv);
-        }
-
-        // check argument, all types of parameters
-        Ast::FunctionParameters fnParas = fnStruct.paras;
-        if (fnArgs.getLength() < fnParas.posParas.size() || fnArgs.getLength() > fnParas.size())
-        {
-            static constexpr char ArgumentMismatchErrorName[] = "ArgumentMismatchError";
-            throw EvaluatorError<ArgumentMismatchErrorName>(FStringView(std::format("Function '{}' expects {} to {} arguments, but {} were provided", fnName.toBasicString(), fnParas.posParas.size(), fnParas.size(), fnArgs.getLength())), currentAddressInfo);
-        }
-
-        // positional parameters type check
-        size_t i;
-        for (i = 0; i < fnParas.posParas.size(); i++)
-        {
-            TypeInfo expectedType(fnParas.posParas[i].second); // look up type info, if exists a type with the name, use it, else throw
-            ObjectPtr argVal = eval(fnArgs.argv[i]);
-            TypeInfo actualType = argVal->getTypeInfo();
-            if (expectedType != actualType and expectedType != ValueType::Any)
-            {
-                static constexpr char ArgumentTypeMismatchErrorName[] = "ArgumentTypeMismatchError";
-                throw EvaluatorError<ArgumentTypeMismatchErrorName>(FStringView(std::format("In function '{}', argument '{}' expects type '{}', but got type '{}'", fnName.toBasicString(), fnParas.posParas[i].first.toBasicString(), expectedType.toString().toBasicString(), actualType.toString().toBasicString())), currentAddressInfo);
-            }
-            evaluatedArgs.argv.push_back(argVal);
-        }
-        // default parameters type check
-        for (; i < fnArgs.getLength(); i++)
-        {
-            size_t defParamIndex = i - fnParas.posParas.size();
-            TypeInfo expectedType = fnParas.defParas[defParamIndex].second.first;
-
-            ObjectPtr defaultVal = eval(fnParas.defParas[defParamIndex].second.second);
-            if (expectedType != defaultVal->getTypeInfo() and expectedType != ValueType::Any)
-            {
-                static constexpr char DefaultParameterTypeErrorName[] = "DefaultParameterTypeError";
-                throw EvaluatorError<DefaultParameterTypeErrorName>(FStringView(std::format("In function '{}', default parameter '{}' has type '{}', which does not match the expected type '{}'", fnName.toBasicString(), fnParas.defParas[defParamIndex].first.toBasicString(), defaultVal->getTypeInfo().toString().toBasicString(), expectedType.toString().toBasicString())), currentAddressInfo);
-            }
-
-            ObjectPtr argVal = eval(fnArgs.argv[i]);
-            TypeInfo actualType = argVal->getTypeInfo();
-            if (expectedType != actualType and expectedType != ValueType::Any)
-            {
-                static constexpr char ArgumentTypeMismatchErrorName[] = "ArgumentTypeMismatchError";
-                throw EvaluatorError<ArgumentTypeMismatchErrorName>(FStringView(std::format("In function '{}', argument '{}' expects type '{}', but got type '{}'", fnName.toBasicString(), fnParas.defParas[defParamIndex].first.toBasicString(), expectedType.toString().toBasicString(), actualType.toString().toBasicString())), currentAddressInfo);
-            }
-            evaluatedArgs.argv.push_back(argVal);
-        }
-        // default parameters filling
-        for (; i < fnParas.size(); i++)
-        {
-            size_t defParamIndex = i - fnParas.posParas.size();
-            ObjectPtr defaultVal = eval(fnParas.defParas[defParamIndex].second.second);
-            evaluatedArgs.argv.push_back(defaultVal);
-        }
-        // create new context for function call
-        auto newContext = std::make_shared<Context>(FString(std::format("<Function {}()>", fnName.toBasicString())),
-                                                    fnStruct.closureContext);
-        auto previousContext = currentContext;
-        currentContext = newContext;
-        // define parameters in new context
-        for (size_t j = 0; j < fnParas.size(); j++)
-        {
-            FString paramName;
-            TypeInfo paramType;
-            if (j < fnParas.posParas.size())
-            {
-                paramName = fnParas.posParas[j].first;
-                paramType = fnParas.posParas[j].second;
-            }
-            else
-            {
-                size_t defParamIndex = j - fnParas.posParas.size();
-                paramName = fnParas.defParas[defParamIndex].first;
-                paramType = fnParas.defParas[defParamIndex].second.first;
-            }
-            AccessModifier argAm = AccessModifier::Const;
-            currentContext->def(paramName, paramType, argAm, evaluatedArgs.argv[j]);
-        }
-        // execute function body
-        ObjectPtr retVal = Object::getNullInstance();
-        for (const auto &stmt : fnStruct.body->stmts)
-        {
-            StatementResult sr = evalStatement(stmt);
-            if (sr.shouldReturn())
-            {
-                retVal = sr.result;
-                break;
-            }
-        }
-        currentContext = previousContext;
-        if (fnStruct.retType != retVal->getTypeInfo() and fnStruct.retType != ValueType::Any)
-        {
-            static constexpr char ReturnTypeMismatchErrorName[] = "ReturnTypeMismatchError";
-            throw EvaluatorError<ReturnTypeMismatchErrorName>(FStringView(std::format("Function '{}' expects return type '{}', but got type '{}'", fnName.toBasicString(), fnStruct.retType.toString().toBasicString(), retVal->getTypeInfo().toString().toBasicString())), currentAddressInfo);
-        }
-        return retVal;
-    }
-
-    ObjectPtr Evaluator::eval(Ast::Expression exp)
-    {
-        using Fig::Ast::AstType;
-        switch (exp->getType())
-        {
-            case AstType::ValueExpr: {
-                auto valExp = std::dynamic_pointer_cast<Ast::ValueExprAst>(exp);
-                return valExp->val;
-            }
-            case AstType::VarExpr: {
-                auto varExp = std::dynamic_pointer_cast<Ast::VarExprAst>(exp);
-                auto val = currentContext->get(varExp->name);
-                if (val.has_value())
-                {
-                    return val.value();
-                }
-                static constexpr char UndefinedVariableErrorName[] = "UndefinedVariableError";
-                throw EvaluatorError<UndefinedVariableErrorName>(FStringView(std::format("Variable '{}' is not defined in the current scope", varExp->name.toBasicString())), varExp->getAAI());
-            }
-            case AstType::BinaryExpr: {
-                auto binExp = std::dynamic_pointer_cast<Ast::BinaryExprAst>(exp);
-                return evalBinary(binExp);
-            }
-            case AstType::UnaryExpr: {
-                auto unExp = std::dynamic_pointer_cast<Ast::UnaryExprAst>(exp);
-                return evalUnary(unExp);
-            }
-            case AstType::FunctionCall: {
-                auto fnCall = std::dynamic_pointer_cast<Ast::FunctionCallExpr>(exp);
-
-                ObjectPtr calleeVal = eval(fnCall->callee);
-
-                if (!calleeVal->is<Function>())
-                {
-                    static constexpr char NotAFunctionErrorName[] = "NotAFunctionError";
-                    throw EvaluatorError<NotAFunctionErrorName>(
-                        FStringView(std::format(
-                            "'{}' is not a function or callable",
-                            calleeVal->toString().toBasicString())),
-                        currentAddressInfo);
-                }
-
-                Function fn = calleeVal->as<Function>();
-
-                FString fnName = u8"<anonymous>";
-                if (auto var = std::dynamic_pointer_cast<Ast::VarExprAst>(fnCall->callee))
-                    fnName = var->name; // try to get function name
-
-                return evalFunctionCall(fn, fnCall->arg, fnName);
-            }
-
-            case AstType::FunctionLiteralExpr: {
-                auto fn = std::dynamic_pointer_cast<Ast::FunctionLiteralExprAst>(exp);
-
-                if (fn->isExprMode())
-                {
-                    Ast::BlockStatement body = std::make_shared<Ast::BlockStatementAst>();
-                    body->setAAI(fn->getExprBody()->getAAI());
-                    Ast::Statement retSt = std::make_shared<Ast::ReturnSt>(fn->getExprBody());
-                    retSt->setAAI(fn->getExprBody()->getAAI());
-                    body->stmts.push_back(retSt);
-                    return std::make_shared<Object>(Function(
-                        fn->paras,
-                        ValueType::Any,
-                        body,
-                        currentContext));
-                }
-                else
-                {
-                    Ast::BlockStatement body = fn->getBlockBody();
-                    return std::make_shared<Object>(Function(
-                        fn->paras,
-                        ValueType::Any,
-                        body,
-                        currentContext));
-                }
-            }
-            case AstType::InitExpr: {
-                auto initExpr = std::dynamic_pointer_cast<Ast::InitExprAst>(exp);
-                if (!currentContext->contains(initExpr->structName))
-                {
-                    static constexpr char StructNotFoundErrorName[] = "StructNotFoundError";
-                    throw EvaluatorError<StructNotFoundErrorName>(FStringView(std::format("Structure type '{}' not found", initExpr->structName.toBasicString())), initExpr->getAAI());
-                }
-                ObjectPtr structTypeVal = currentContext->get(initExpr->structName).value();
-                if (!structTypeVal->is<StructType>())
-                {
-                    static constexpr char NotAStructTypeErrorName[] = "NotAStructTypeError";
-                    throw EvaluatorError<NotAStructTypeErrorName>(FStringView(std::format("'{}' is not a structure type", initExpr->structName.toBasicString())), initExpr->getAAI());
-                }
-                const StructType &structT = structTypeVal->as<StructType>();
-                ContextPtr defContext = structT.defContext; // definition context
-                // check init args
-
-                size_t minArgs = 0;
-                size_t maxArgs = structT.fields.size();
-
-                for (auto &f : structT.fields)
-                {
-                    if (f.defaultValue == nullptr) minArgs++;
-                }
-
-                size_t got = initExpr->args.size();
-                if (got > maxArgs || got < minArgs)
-                {
-                    static constexpr char StructInitArgumentMismatchErrorName[] = "StructInitArgumentMismatchError";
-                    throw EvaluatorError<StructInitArgumentMismatchErrorName>(FStringView(std::format("Structure '{}' expects {} to {} fields, but {} were provided", initExpr->structName.toBasicString(), minArgs, maxArgs, initExpr->args.size())), initExpr->getAAI());
-                }
-
-                std::vector<std::pair<FString, ObjectPtr>> evaluatedArgs;
-                for (const auto &[argName, argExpr] : initExpr->args)
-                {
-                    evaluatedArgs.push_back({argName, eval(argExpr)});
-                }
-                ContextPtr instanceCtx = std::make_shared<Context>(
-                    FString(std::format("<StructInstance {}>", initExpr->structName.toBasicString())),
-                    currentContext);
-                /*
-                    3 ways of calling constructor
-                    .1 Person {"Fig", 1, "IDK"};
-                    .2 Person {name: "Fig", age: 1, sex: "IDK"}; // can be unordered
-                    .3 Person {name, age, sex};
-                */
-                {
-                    using enum Ast::InitExprAst::InitMode;
-                    if (initExpr->initMode == Positional)
-                    {
-                        for (size_t i = 0; i < maxArgs; ++i)
-                        {
-                            const Field &field = structT.fields[i];
-                            const FString &fieldName = field.name;
-                            const TypeInfo &expectedType = field.type;
-                            if (i >= evaluatedArgs.size())
-                            {
-                                // we've checked argument count before, so here must be a default value
-                                ContextPtr previousContext = currentContext;
-                                currentContext = defContext; // evaluate default value in definition context
-
-                                ObjectPtr defaultVal = eval(field.defaultValue); // it can't be null here
-
-                                currentContext = previousContext;
-
-                                // type check
-                                if (expectedType != defaultVal->getTypeInfo() && expectedType != ValueType::Any)
-                                {
-                                    static constexpr char StructFieldTypeMismatchErrorName[] = "StructFieldTypeMismatchError";
-                                    throw EvaluatorError<StructFieldTypeMismatchErrorName>(FStringView(std::format("In structure '{}', field '{}' expects type '{}', but got type '{}'", initExpr->structName.toBasicString(), fieldName.toBasicString(), expectedType.toString().toBasicString(), defaultVal->getTypeInfo().toString().toBasicString())), initExpr->getAAI());
-                                }
-
-                                instanceCtx->def(fieldName, expectedType, field.am, defaultVal);
-                                continue;
-                            }
-
-                            const ObjectPtr &argVal = evaluatedArgs[i].second;
-                            if (expectedType != argVal->getTypeInfo() && expectedType != ValueType::Any)
-                            {
-                                static constexpr char StructFieldTypeMismatchErrorName[] = "StructFieldTypeMismatchError";
-                                throw EvaluatorError<StructFieldTypeMismatchErrorName>(FStringView(std::format("In structure '{}', field '{}' expects type '{}', but got type '{}'", initExpr->structName.toBasicString(), fieldName.toBasicString(), expectedType.toString().toBasicString(), argVal->getTypeInfo().toString().toBasicString())), initExpr->getAAI());
-                            }
-                            instanceCtx->def(fieldName, expectedType, field.am, argVal);
-                        }
-                    }
-                    else
-                    {
-                        // named / shorthand init
-                        for (size_t i = 0; i < maxArgs; ++i)
-                        {
-                            const Field &field = structT.fields[i];
-                            const FString &fieldName = (field.name.empty() ? evaluatedArgs[i].first : field.name);
-                            if (instanceCtx->containsInThisScope(fieldName))
-                            {
-                                static constexpr char StructFieldRedeclarationErrorName[] = "StructFieldRedeclarationError";
-                                throw EvaluatorError<StructFieldRedeclarationErrorName>(FStringView(std::format("Field '{}' already initialized in structure '{}'", fieldName.toBasicString(), initExpr->structName.toBasicString())), initExpr->getAAI());
-                            }
-                            if (i + 1 > got)
-                            {
-                                // use default value
-                                ContextPtr previousContext = currentContext;
-                                currentContext = defContext;                     // evaluate default value in definition context
-                                ObjectPtr defaultVal = eval(field.defaultValue); // it can't be null here
-                                currentContext = previousContext;
-
-                                // type check
-                                const TypeInfo &expectedType = field.type;
-                                if (expectedType != defaultVal->getTypeInfo() && expectedType != ValueType::Any)
-                                {
-                                    static constexpr char StructFieldTypeMismatchErrorName[] = "StructFieldTypeMismatchError";
-                                    throw EvaluatorError<StructFieldTypeMismatchErrorName>(FStringView(std::format("In structure '{}', field '{}' expects type '{}', but got type '{}'", initExpr->structName.toBasicString(), fieldName.toBasicString(), expectedType.toString().toBasicString(), defaultVal->getTypeInfo().toString().toBasicString())), initExpr->getAAI());
-                                }
-
-                                instanceCtx->def(fieldName, field.type, field.am, defaultVal);
-                                continue;
-                            }
-                            const ObjectPtr &argVal = evaluatedArgs[i].second;
-                            if (field.type != argVal->getTypeInfo() && field.type != ValueType::Any)
-                            {
-                                static constexpr char StructFieldTypeMismatchErrorName[] = "StructFieldTypeMismatchError";
-                                throw EvaluatorError<StructFieldTypeMismatchErrorName>(FStringView(std::format("In structure '{}', field '{}' expects type '{}', but got type '{}'", initExpr->structName.toBasicString(), fieldName.toBasicString(), field.type.toString().toBasicString(), argVal->getTypeInfo().toString().toBasicString())), initExpr->getAAI());
-                            }
-                            instanceCtx->def(fieldName, field.type, field.am, argVal);
-                        }
-                    }
-                }
-                instanceCtx->merge(*structT.defContext);
-                for (auto &[id, fn] : instanceCtx->getFunctions())
-                {
-                    instanceCtx->_update(*instanceCtx->getFunctionName(id), Object(
-                                                                                Function(fn.paras, fn.retType, fn.body, instanceCtx) // change its closureContext to struct instance's context
-                                                                                ));
-                }
-                return std::make_shared<Object>(StructInstance(structT.id, instanceCtx));
-            }
-            default:
-                throw RuntimeError(FStringView("Unknown expression type:" + std::to_string(static_cast<int>(exp->getType()))));
-                return Object::getNullInstance();
-        }
-    }
-    StatementResult Evaluator::evalBlockStatement(const Ast::BlockStatement &blockSt, ContextPtr context)
-    {
-        auto previousContext = currentContext;
-        if (context)
-        {
-            currentContext = context;
-        }
-        else
-        {
-            currentContext = std::make_shared<Context>(FString(std::format("<Block {}:{}>", blockSt->getAAI().line, blockSt->getAAI().column)), currentContext);
-        }
-        StatementResult lstResult = StatementResult::normal();
-        for (const auto &s : blockSt->stmts)
-        {
-            StatementResult sr = evalStatement(s);
-            if (!sr.isNormal())
-            {
-                lstResult = sr;
-                break;
-            }
-        }
-        currentContext = previousContext;
-        return lstResult;
-    }
-    StatementResult Evaluator::evalStatement(const Ast::Statement &stmt)
-    {
-        using Fig::Ast::AstType;
-        currentAddressInfo = stmt->getAAI();
-        switch (stmt->getType())
-        {
-            case AstType::VarDefSt: {
-                auto varDef = std::dynamic_pointer_cast<Ast::VarDefAst>(stmt);
-                if (currentContext->contains(varDef->name))
-                {
-                    static constexpr char RedeclarationErrorName[] = "RedeclarationError";
-                    throw EvaluatorError<RedeclarationErrorName>(FStringView(std::format("Variable '{}' already defined in this scope", varDef->name.toBasicString())), currentAddressInfo);
-                }
-                ObjectPtr val;
-                TypeInfo varTypeInfo;
-                if (varDef->typeName == Parser::varDefTypeFollowed)
-                {
-                    // has expr
-                    val = eval(varDef->expr);
-                    varTypeInfo = val->getTypeInfo();
-                }
-                else if (varDef->expr)
-                {
-                    val = eval(varDef->expr);
-                    if (varDef->typeName != ValueType::Any.name)
-                    {
-                        TypeInfo expectedType(varDef->typeName);
-                        TypeInfo actualType = val->getTypeInfo();
-                        if (expectedType != actualType and expectedType != ValueType::Any)
-                        {
-                            static constexpr char VariableTypeMismatchErrorName[] = "VariableTypeMismatchError";
-                            throw EvaluatorError<VariableTypeMismatchErrorName>(FStringView(std::format("Variable '{}' expects type '{}', but got type '{}'", varDef->name.toBasicString(), expectedType.toString().toBasicString(), actualType.toString().toBasicString())), varDef->getAAI());
-                        }
-                    }
-                }
-                else if (!varDef->typeName.empty())
-                {
-                    varTypeInfo = TypeInfo(varDef->typeName); // may throw
-                    val = std::make_shared<Object>(Object::defaultValue(varTypeInfo));
-                }
-                AccessModifier am = (varDef->isPublic ? (varDef->isConst ? AccessModifier::PublicConst : AccessModifier::Public) : (varDef->isConst ? AccessModifier::Const : AccessModifier::Normal));
-                currentContext->def(varDef->name, varTypeInfo, am, val);
-                return StatementResult::normal();
-            }
-            case AstType::ExpressionStmt: {
-                auto exprSt = std::dynamic_pointer_cast<Ast::ExpressionStmtAst>(stmt);
-                eval(exprSt->exp);
-                return StatementResult::normal();
-            };
-            case AstType::BlockStatement: {
-                auto blockSt = std::dynamic_pointer_cast<Ast::BlockStatementAst>(stmt);
-                return evalBlockStatement(blockSt); // auto create new context in block statement
-            };
-            case AstType::FunctionDefSt: {
-                auto fnDef = std::dynamic_pointer_cast<Ast::FunctionDefSt>(stmt);
-                if (currentContext->containsInThisScope(fnDef->name))
-                {
-                    static constexpr char RedeclarationErrorName[] = "RedeclarationError";
-                    throw EvaluatorError<RedeclarationErrorName>(FStringView(std::format("Function '{}' already defined in this scope", fnDef->name.toBasicString())), currentAddressInfo);
-                }
-                AccessModifier am = (fnDef->isPublic ? AccessModifier::PublicConst : AccessModifier::Const);
-                currentContext->def(
-                    fnDef->name,
-                    ValueType::Function,
-                    am,
-                    std::make_shared<Object>(Function(
-                        fnDef->paras,
-                        TypeInfo(fnDef->retType),
-                        fnDef->body,
-                        currentContext)));
-                return StatementResult::normal();
-            };
-            case AstType::StructSt: {
-                auto stDef = std::dynamic_pointer_cast<Ast::StructDefSt>(stmt);
-                if (currentContext->containsInThisScope(stDef->name))
-                {
-                    static constexpr char RedeclarationErrorName[] = "RedeclarationError";
-                    throw EvaluatorError<RedeclarationErrorName>(FStringView(std::format("Structure '{}' already defined in this scope", stDef->name.toBasicString())), currentAddressInfo);
-                }
-                std::vector<Field> fields;
-                std::vector<FString> _fieldNames;
-                for (Ast::StructDefField field : stDef->fields)
-                {
-                    if (Utils::vectorContains(field.fieldName, _fieldNames))
-                    {
-                        static constexpr char RedeclarationErrorName[] = "RedeclarationError";
-                        throw EvaluatorError<RedeclarationErrorName>(FStringView(std::format("Field '{}' already defined in structure '{}'", field.fieldName.toBasicString(), stDef->name.toBasicString())), currentAddressInfo);
-                    }
-                    fields.push_back(Field(field.am, field.fieldName, TypeInfo(field.tiName), field.defaultValueExpr));
-                }
-                ContextPtr defContext = std::make_shared<Context>(FString(std::format("<Struct {} at {}:{}>",
-                                                                                      stDef->name.toBasicString(),
-                                                                                      stDef->getAAI().line,
-                                                                                      stDef->getAAI().column)),
-                                                                  currentContext);
-                ContextPtr previousContext = currentContext;
-                currentContext = defContext;
-
-                const Ast::BlockStatement &body = stDef->body;
-                for (auto &st : body->stmts)
-                {
-                    if (st->getType() != Ast::AstType::FunctionDefSt)
-                    {
-                        static constexpr char UnexpectedStatementInStructError[] = "UnexpectedStatementInStructError";
-                        throw EvaluatorError<UnexpectedStatementInStructError>(FStringView(
-                                                                                   std::format("Unexpected statement `{}` in struct declaration",
-                                                                                               st->toString().toBasicString())),
-                                                                               st->getAAI());
-                    }
-                    evalStatement(st); // function def st
-                }
-                currentContext = previousContext;
-
-                AccessModifier am = (stDef->isPublic ? AccessModifier::PublicConst : AccessModifier::Const);
-                TypeInfo _(stDef->name, true); // register type name
-                currentContext->def(
-                    stDef->name,
-                    ValueType::StructType,
-                    am,
-                    std::make_shared<Object>(StructType(
-                        defContext,
-                        fields)));
-                return StatementResult::normal();
-            }
-            // case AstType::VarAssignSt: {
-            //     auto varAssign = std::dynamic_pointer_cast<Ast::VarAssignSt>(stmt);
-            //     if (!currentContext->contains(varAssign->varName))
-            //     {
-            //         static constexpr char VariableNotFoundErrorName[] = "VariableNotFoundError";
-            //         throw EvaluatorError<VariableNotFoundErrorName>(FStringView(std::format("Variable '{}' not defined", varAssign->varName.toBasicString())), currentAddressInfo);
-            //     }
-            //     if (!currentContext->isVariableMutable(varAssign->varName))
-            //     {
-            //         static constexpr char ConstAssignmentErrorName[] = "ConstAssignmentError";
-            //         throw EvaluatorError<ConstAssignmentErrorName>(FStringView(std::format("Cannot assign to constant variable '{}'", varAssign->varName.toBasicString())), currentAddressInfo);
-            //     }
-            //     Object val = eval(varAssign->valueExpr);
-            //     if (currentContext->getTypeInfo(varAssign->varName) != ValueType::Any)
-            //     {
-            //         TypeInfo expectedType = currentContext->getTypeInfo(varAssign->varName);
-            //         TypeInfo actualType = val.getTypeInfo();
-            //         if (expectedType != actualType)
-            //         {
-            //             static constexpr char VariableTypeMismatchErrorName[] = "VariableTypeMismatchError";
-            //             throw EvaluatorError<VariableTypeMismatchErrorName>(FStringView(std::format("assigning: Variable '{}' expects type '{}', but got type '{}'", varAssign->varName.toBasicString(), expectedType.toString().toBasicString(), actualType.toString().toBasicString())), currentAddressInfo);
-            //         }
-            //     }
-            //     currentContext->set(varAssign->varName, val);
-            //     return StatementResult::normal();
-            // };
-            case AstType::IfSt: {
-                auto ifSt = std::dynamic_pointer_cast<Ast::IfSt>(stmt);
-                ObjectPtr condVal = eval(ifSt->condition);
-                if (condVal->getTypeInfo() != ValueType::Bool)
-                {
-                    static constexpr char ConditionTypeErrorName[] = "ConditionTypeError";
-                    throw EvaluatorError<ConditionTypeErrorName>(FStringView(u8"If condition must be boolean"), currentAddressInfo);
-                }
-                if (condVal->as<ValueType::BoolClass>())
-                {
-                    return evalBlockStatement(ifSt->body);
-                }
-                // else
-                for (const auto &elif : ifSt->elifs)
-                {
-                    ObjectPtr elifCondVal = eval(elif->condition);
-                    if (elifCondVal->getTypeInfo() != ValueType::Bool)
-                    {
-                        static constexpr char ConditionTypeErrorName[] = "ConditionTypeError";
-                        throw EvaluatorError<ConditionTypeErrorName>(FStringView(u8"Else-if condition must be boolean"), currentAddressInfo);
-                    }
-                    if (elifCondVal->as<ValueType::BoolClass>())
-                    {
-                        return evalBlockStatement(elif->body);
-                    }
-                }
-                if (ifSt->els)
-                {
-                    return evalBlockStatement(ifSt->els->body);
-                }
-                return StatementResult::normal();
-            };
-            case AstType::WhileSt: {
-                auto whileSt = std::dynamic_pointer_cast<Ast::WhileSt>(stmt);
-                while (true)
-                {
-                    ObjectPtr condVal = eval(whileSt->condition);
-                    if (condVal->getTypeInfo() != ValueType::Bool)
-                    {
-                        static constexpr char ConditionTypeErrorName[] = "ConditionTypeError";
-                        throw EvaluatorError<ConditionTypeErrorName>(FStringView(u8"While condition must be boolean"), whileSt->condition->getAAI());
-                    }
-                    if (!condVal->as<ValueType::BoolClass>())
-                    {
-                        break;
-                    }
-                    ContextPtr loopContext = std::make_shared<Context>(
-                        FString(std::format("<While {}:{}>",
-                                            whileSt->getAAI().line, whileSt->getAAI().column)),
-                        currentContext); // every loop has its own context
-                    StatementResult sr = evalBlockStatement(whileSt->body, loopContext);
-                    if (sr.shouldReturn())
-                    {
-                        return sr;
-                    }
-                    if (sr.shouldBreak())
-                    {
-                        break;
-                    }
-                    if (sr.shouldContinue())
-                    {
-                        continue;
-                    }
-                }
-                return StatementResult::normal();
-            };
-            case AstType::ForSt: {
-                auto forSt = std::dynamic_pointer_cast<Ast::ForSt>(stmt);
-                ContextPtr loopContext = std::make_shared<Context>(
-                    FString(std::format("<For {}:{}>",
-                                        forSt->getAAI().line, forSt->getAAI().column)),
-                    currentContext); // for loop has its own context
-                ContextPtr previousContext = currentContext;
-                currentContext = loopContext;
-
-                evalStatement(forSt->initSt); // ignore init statement result
-                size_t iteration = 0;
-
-                while (true) // use while loop to simulate for loop, cause we need to check condition type every iteration
-                {
-                    ObjectPtr condVal = eval(forSt->condition);
-                    if (condVal->getTypeInfo() != ValueType::Bool)
-                    {
-                        static constexpr char ConditionTypeErrorName[] = "ConditionTypeError";
-                        throw EvaluatorError<ConditionTypeErrorName>(FStringView(u8"For condition must be boolean"), forSt->condition->getAAI());
-                    }
-                    if (!condVal->as<ValueType::BoolClass>())
-                    {
-                        break;
-                    }
-                    iteration++;
-                    ContextPtr iterationContext = std::make_shared<Context>(
-                        FString(std::format("<For {}:{}, Iteration {}>",
-                                            forSt->getAAI().line, forSt->getAAI().column, iteration)),
-                        loopContext); // every loop has its own context
-                    StatementResult sr = evalBlockStatement(forSt->body, iterationContext);
-                    if (sr.shouldReturn())
-                    {
-                        currentContext = previousContext; // restore context before return
-                        return sr;
-                    }
-                    if (sr.shouldBreak())
-                    {
-                        break;
-                    }
-                    if (sr.shouldContinue())
-                    {
-                        // continue to next iteration
-                        continue;
-                    }
-                    currentContext = loopContext;      // let increment statement be in loop context
-                    evalStatement(forSt->incrementSt); // ignore increment statement result
-                }
-                currentContext = previousContext; // restore context
-                return StatementResult::normal();
-            }
-            case AstType::ReturnSt: {
-                if (!currentContext->parent)
-                {
-                    static constexpr char ReturnOutsideFunctionErrorName[] = "ReturnOutsideFunctionError";
-                    throw EvaluatorError<ReturnOutsideFunctionErrorName>(FStringView(u8"'return' statement outside function"), currentAddressInfo);
-                }
-                if (!currentContext->isInFunctionContext())
-                {
-                    static constexpr char ReturnOutsideFunctionErrorName[] = "ReturnOutsideFunctionError";
-                    throw EvaluatorError<ReturnOutsideFunctionErrorName>(FStringView(u8"'return' statement outside function"), currentAddressInfo);
-                }
-                auto returnSt = std::dynamic_pointer_cast<Ast::ReturnSt>(stmt);
-                return StatementResult::returnFlow(eval(returnSt->retValue));
-            };
-            case AstType::BreakSt: {
-                if (!currentContext->parent)
-                {
-                    static constexpr char BreakOutsideLoopErrorName[] = "BreakOutsideLoopError";
-                    throw EvaluatorError<BreakOutsideLoopErrorName>(FStringView(u8"'break' statement outside loop"), currentAddressInfo);
-                }
-                if (!currentContext->isInLoopContext())
-                {
-                    static constexpr char BreakOutsideLoopErrorName[] = "BreakOutsideLoopError";
-                    throw EvaluatorError<BreakOutsideLoopErrorName>(FStringView(u8"'break' statement outside loop"), currentAddressInfo);
-                }
-                return StatementResult::breakFlow();
-            };
-            case AstType::ContinueSt: {
-                if (!currentContext->parent)
-                {
-                    static constexpr char ContinueOutsideLoopErrorName[] = "ContinueOutsideLoopError";
-                    throw EvaluatorError<ContinueOutsideLoopErrorName>(FStringView(u8"'continue' statement outside loop"), currentAddressInfo);
-                }
-                if (!currentContext->isInLoopContext())
-                {
-                    static constexpr char ContinueOutsideLoopErrorName[] = "ContinueOutsideLoopError";
-                    throw EvaluatorError<ContinueOutsideLoopErrorName>(FStringView(u8"'continue' statement outside loop"), currentAddressInfo);
-                }
-                return StatementResult::continueFlow();
-            };
-            default:
-                throw RuntimeError(FStringView(std::string("Unknown statement type:") + magic_enum::enum_name(stmt->getType()).data()));
-        }
-        return StatementResult::normal();
-    }
-
-    void Evaluator::run()
-    {
-        for (auto ast : asts)
-        {
-            currentAddressInfo = ast->getAAI();
-            if (std::dynamic_pointer_cast<Ast::ExpressionStmtAst>(ast))
-            {
-                auto exprAst = std::dynamic_pointer_cast<Ast::ExpressionStmtAst>(ast);
-                Ast::Expression exp = exprAst->exp;
-                eval(exp);
-            }
-            else if (dynamic_cast<Ast::StatementAst *>(ast.get()))
-            {
-                auto stmtAst = std::dynamic_pointer_cast<Ast::StatementAst>(ast);
-                evalStatement(stmtAst);
-            }
-            else
-            {
-                throw RuntimeError(FStringView(u8"Unknown AST type"));
-            }
-        }
-    }
-
-    void Evaluator::printStackTrace() const
-    {
-        if (currentContext)
-            currentContext->printStackTrace();
-        else
-            std::cerr << "[STACK TRACE] (No context has been loaded)\n";
-    }
-} // namespace Fig

src/main.cpp

@@ -27,16 +27,16 @@ Copyright (C) 2020-2025 PuqiAR
 This software is licensed under the MIT License. See LICENSE.txt for details.
 */
 
-#include <argparse/argparse.hpp>
+#include <Utils/argparse/argparse.hpp>
 #include <print>
 #include <fstream>
 
-#include <core.hpp>
-#include <lexer.hpp>
-#include <parser.hpp>
-#include <evaluator.hpp>
-#include <AstPrinter.hpp>
-#include <errorLog.hpp>
+#include <Core/core.hpp>
+#include <Lexer/lexer.hpp>
+#include <Parser/parser.hpp>
+#include <Evaluator/evaluator.hpp>
+#include <Utils/AstPrinter.hpp>
+#include <Error/errorLog.hpp>
 
 static size_t addressableErrorCount = 0;
 static size_t unaddressableErrorCount = 0;
@@ -117,13 +117,13 @@ int main(int argc, char **argv)
     // }
 
     Fig::Parser parser(lexer);
-    std::vector<Fig::Ast::AstBase> ast;
+    std::vector<Fig::Ast::AstBase> asts;
 
     std::vector<FString> sourceLines = splitSource(Fig::FString(source));
 
     try
     {
-        ast = parser.parseAll();
+        asts = parser.parseAll();
     }
     catch (const Fig::AddressableError &e)
     {
@@ -150,10 +150,12 @@ int main(int argc, char **argv)
     //     printer.print(node);
     // }
 
-    Fig::Evaluator evaluator(ast);
+    Fig::Evaluator evaluator;
+    evaluator.CreateGlobalContext();
+    evaluator.RegisterBuiltins();
     try
     {
-        evaluator.run();
+        evaluator.Run(asts);
     }
     catch (const Fig::AddressableError &e)
     {

test.fig

@@ -1,14 +1,15 @@
-struct test
+struct Person
 {
-    bar:String = "1233";
-    func foo()
+    name: String;
+
+    func getName() -> String
     {
-        __fstdout_println(bar);
+        return name;
     }
 }
 
-var x := test{};
-x.foo();
+var person := Person{"PuqiAR"};
 
-x.bar = "555";
-x.foo();
+const print := __fstdout_println;
+
+print(person.getName());

xmake.lua

@@ -13,9 +13,14 @@ target("Fig")
     add_cxxflags("-static")
     add_cxxflags("-stdlib=libc++")
 
-    add_files("src/*.cpp")
+    add_files("src/main.cpp")
+    add_files("src/Core/warning.cpp")
+    add_files("src/Evaluator/evaluator.cpp")
+    add_files("src/Lexer/lexer.cpp")
+    add_files("src/Parser/parser.cpp")
+    add_files("src/Value/value.cpp")
     
-    add_includedirs("include")
+    add_includedirs("src")
 
     set_warnings("all")