4 files changed, 349 insertions, 105 deletions

diff --git a/spec/inputs/cond.yue b/spec/inputs/cond.yue
index df7d78e..f5f42a8 100644
--- a/spec/inputs/cond.yue
+++ b/spec/inputs/cond.yue
@@ -237,6 +237,28 @@ do
 
         evaluation = v(1) > v(2) <= v(3)
 
+do
+        a = v(1) < v(2) < v(3) < v(4)
+        a = x and y or v(1) < v(2) < v(3) < v(4)
+        a = v(1) < v(2) < v(3) < v(4) or x and y
+        a = x and y or v(1) < v(2) < v(3) < v(4) or w and z
+
+        a = v(1) < v(2) < v(3) and b < v(4) < v(5) < v(6)
+        a = x and y or v(1) < v(2) < v(3) and b < v(4) < v(5) < v(6)
+        a = v(1) < v(2) < v(3) and b < v(4) < v(5) < v(6) or x and y
+        a = x and y or v(1) < v(2) < v(3) and b < v(4) < v(5) < v(6) or w and z
+
+        local v1, v2, v3, v4, v5, v6
+        a = v1 < v2 < v3 < v4
+        a = x and y or v1 < v2 < v3 < v4
+        a = v1 < v2 < v3 < v4 or x and y
+        a = x and y or v1 < v2 < v3 < v4 or w and z
+
+        a = v1 < v2 < v3 and b < v4 < v5 < v6
+        a = x and y or v1 < v2 < v3 and b < v4 < v5 < v6
+        a = v1 < v2 < v3 and b < v4 < v5 < v6 or x and y
+        a = x and y or v1 < v2 < v3 and b < v4 < v5 < v6 or w and z
+
 nil
 
 
diff --git a/spec/outputs/cond.lua b/spec/outputs/cond.lua
index 651c14a..d7aae02 100644
--- a/spec/outputs/cond.lua
+++ b/spec/outputs/cond.lua
@@ -355,11 +355,162 @@ do
         local evaluation
         do
                 local _cond_0 = v(2)
-                evaluation = v(1) < _cond_0 and _cond_0 <= v(3)
+                if not (v(1) < _cond_0) then
+                        evaluation = false
+                else
+                        evaluation = _cond_0 <= v(3)
+                end
+        end
+        do
+                local _cond_0 = v(2)
+                if not (v(1) > _cond_0) then
+                        evaluation = false
+                else
+                        evaluation = _cond_0 <= v(3)
+                end
         end
+end
+do
         do
                 local _cond_0 = v(2)
-                evaluation = v(1) > _cond_0 and _cond_0 <= v(3)
+                if not (v(1) < _cond_0) then
+                        a = false
+                else
+                        local _cond_1 = v(3)
+                        if not (_cond_0 < _cond_1) then
+                                a = false
+                        else
+                                a = _cond_1 < v(4)
+                        end
+                end
         end
+        a = x and y or (function()
+                local _cond_0 = v(2)
+                if not (v(1) < _cond_0) then
+                        return false
+                else
+                        local _cond_1 = v(3)
+                        if not (_cond_0 < _cond_1) then
+                                return false
+                        else
+                                return _cond_1 < v(4)
+                        end
+                end
+        end)()
+        a = (function()
+                local _cond_0 = v(2)
+                if not (v(1) < _cond_0) then
+                        return false
+                else
+                        local _cond_1 = v(3)
+                        if not (_cond_0 < _cond_1) then
+                                return false
+                        else
+                                return _cond_1 < v(4)
+                        end
+                end
+        end)() or x and y
+        a = x and y or (function()
+                local _cond_0 = v(2)
+                if not (v(1) < _cond_0) then
+                        return false
+                else
+                        local _cond_1 = v(3)
+                        if not (_cond_0 < _cond_1) then
+                                return false
+                        else
+                                return _cond_1 < v(4)
+                        end
+                end
+        end)() or w and z
+        a = (function()
+                local _cond_0 = v(2)
+                if not (v(1) < _cond_0) then
+                        return false
+                else
+                        return _cond_0 < v(3)
+                end
+        end)() and (function()
+                local _cond_0 = v(4)
+                if not (b < _cond_0) then
+                        return false
+                else
+                        local _cond_1 = v(5)
+                        if not (_cond_0 < _cond_1) then
+                                return false
+                        else
+                                return _cond_1 < v(6)
+                        end
+                end
+        end)()
+        a = x and y or (function()
+                local _cond_0 = v(2)
+                if not (v(1) < _cond_0) then
+                        return false
+                else
+                        return _cond_0 < v(3)
+                end
+        end)() and (function()
+                local _cond_0 = v(4)
+                if not (b < _cond_0) then
+                        return false
+                else
+                        local _cond_1 = v(5)
+                        if not (_cond_0 < _cond_1) then
+                                return false
+                        else
+                                return _cond_1 < v(6)
+                        end
+                end
+        end)()
+        a = (function()
+                local _cond_0 = v(2)
+                if not (v(1) < _cond_0) then
+                        return false
+                else
+                        return _cond_0 < v(3)
+                end
+        end)() and (function()
+                local _cond_0 = v(4)
+                if not (b < _cond_0) then
+                        return false
+                else
+                        local _cond_1 = v(5)
+                        if not (_cond_0 < _cond_1) then
+                                return false
+                        else
+                                return _cond_1 < v(6)
+                        end
+                end
+        end)() or x and y
+        a = x and y or (function()
+                local _cond_0 = v(2)
+                if not (v(1) < _cond_0) then
+                        return false
+                else
+                        return _cond_0 < v(3)
+                end
+        end)() and (function()
+                local _cond_0 = v(4)
+                if not (b < _cond_0) then
+                        return false
+                else
+                        local _cond_1 = v(5)
+                        if not (_cond_0 < _cond_1) then
+                                return false
+                        else
+                                return _cond_1 < v(6)
+                        end
+                end
+        end)() or w and z
+        local v1, v2, v3, v4, v5, v6
+        a = v1 < v2 and v2 < v3 and v3 < v4
+        a = x and y or v1 < v2 and v2 < v3 and v3 < v4
+        a = v1 < v2 and v2 < v3 and v3 < v4 or x and y
+        a = x and y or v1 < v2 and v2 < v3 and v3 < v4 or w and z
+        a = v1 < v2 and v2 < v3 and b < v4 and v4 < v5 and v5 < v6
+        a = x and y or v1 < v2 and v2 < v3 and b < v4 and v4 < v5 and v5 < v6
+        a = v1 < v2 and v2 < v3 and b < v4 and v4 < v5 and v5 < v6 or x and y
+        a = x and y or v1 < v2 and v2 < v3 and b < v4 and v4 < v5 and v5 < v6 or w and z
 end
 return nil
diff --git a/spec/outputs/unicode/cond.lua b/spec/outputs/unicode/cond.lua
index 9a4ccb9..ed5d274 100644
--- a/spec/outputs/unicode/cond.lua
+++ b/spec/outputs/unicode/cond.lua
@@ -361,11 +361,19 @@ do
         local _u6c42_u503c
         do
                 local _cond_0 = _u503c(2)
-                _u6c42_u503c = _u503c(1) < _cond_0 and _cond_0 <= _u503c(3)
+                if not (_u503c(1) < _cond_0) then
+                        _u6c42_u503c = false
+                else
+                        _u6c42_u503c = _cond_0 <= _u503c(3)
+                end
         end
         do
                 local _cond_0 = _u503c(2)
-                _u6c42_u503c = _u503c(1) > _cond_0 and _cond_0 <= _u503c(3)
+                if not (_u503c(1) > _cond_0) then
+                        _u6c42_u503c = false
+                else
+                        _u6c42_u503c = _cond_0 <= _u503c(3)
+                end
         end
 end
 return nil
diff --git a/src/yuescript/yue_compiler.cpp b/src/yuescript/yue_compiler.cpp
index d32d9c1..7ec3b3a 100644
--- a/src/yuescript/yue_compiler.cpp
+++ b/src/yuescript/yue_compiler.cpp
@@ -75,7 +75,7 @@ static std::unordered_set<std::string> Metamethods = {
         "close"s // Lua 5.4
 };
 
-const std::string_view version = "0.20.0"sv;
+const std::string_view version = "0.20.1"sv;
 const std::string_view extension = "yue"sv;
 
 class CompileError : public std::logic_error {
@@ -1207,19 +1207,16 @@ private:
 
         bool isConditionChaining(Exp_t* exp) {
                 int conditionChaining = 0;
-                for (const auto& opValue_ : exp->opValues.objects()) {
+                for (auto opValue_ : exp->opValues.objects()) {
                         auto opValue = static_cast<ExpOpValue_t*>(opValue_);
                         auto op = _parser.toString(opValue->op);
                         if (isConditionChainingOperator(op)) {
                                 conditionChaining++;
-                                if (conditionChaining > 1) {
-                                        return true;
-                                }
-                        } else {
-                                conditionChaining = 0;
+                        } else if (conditionChaining > 0) {
+                                return false;
                         }
                 }
-                return false;
+                return conditionChaining > 1 && conditionChaining == static_cast<int>(exp->opValues.size());
         }
 
         UnaryExp_t* unaryGeneratingAnonFunc(Exp_t* exp) {
@@ -3369,14 +3366,14 @@ private:
                 std::list<std::pair<std::string, ast_list<true, UnaryExp_t>*>> chains;
                 chains.emplace_back(std::string(), &exp->pipeExprs);
                 int conditionChainCount = 0;
-                str_list evalLines;
-                auto checkChains = [&]() {
+                auto checkChains = [&]()-> ast_ptr<false, Exp_t> {
                         std::optional<str_list> result;
                         if (conditionChainCount > 1) {
-                                bool needWrapping = false;
-                                str_list conds;
-                                str_list preDefines;
-                                std::list<std::variant<std::string, ast_ptr<false, Exp_t>>> stack;
+                                ast_ptr<false, Exp_t> newCondExp;
+                                ast_ptr<false, ExpListAssign_t> preDefine;
+                                ast_sel_list<true, IfCond_t, Block_t, Statement_t>* nodes = nullptr;
+                                std::list<std::variant<std::string, ast_list<true, UnaryExp_t>>> stack;
+                                pushScope();
                                 for (const auto& item : chains) {
                                         if (!item.first.empty()) {
                                                 stack.push_back(item.first);
@@ -3393,9 +3390,7 @@ private:
                                                                 if (varName.empty()) {
                                                                         if (auto sval = static_cast<Value_t*>(unary->expos.front())->item.as<SimpleValue_t>()) {
                                                                                 if (ast_is<ConstValue_t, Num_t>(sval->value)) {
-                                                                                        auto condExp = unary->new_ptr<Exp_t>();
-                                                                                        condExp->pipeExprs.dup(*item.second);
-                                                                                        stack.push_back(condExp);
+                                                                                        stack.push_back(*item.second);
                                                                                         goto reduce;
                                                                                 }
                                                                         }
@@ -3404,77 +3399,125 @@ private:
                                                 }
                                                 if (varName.empty() || !isLocal(varName)) {
                                                         varName = getUnusedName("_cond_"sv);
+                                                        addToScope(varName);
                                                         auto condExp = node->new_ptr<Exp_t>();
                                                         condExp->pipeExprs.dup(*item.second);
                                                         auto varExp = toAst<Exp_t>(varName, node);
                                                         auto assignment = assignmentFrom(varExp, condExp, node);
-                                                        if (!needWrapping) {
-                                                                needWrapping = true;
-                                                                if (usage == ExpUsage::Closure) {
-                                                                        pushFunctionScope();
-                                                                        pushAnonVarArg();
-                                                                        pushScope();
-                                                                } else if (usage == ExpUsage::Assignment) {
-                                                                        pushScope();
-                                                                }
-                                                        }
-                                                        transformAssignment(assignment, preDefines);
-                                                        stack.push_back(varExp);
+                                                        preDefine = assignment;
+                                                        stack.push_back(varExp->pipeExprs);
                                                         goto reduce;
                                                 }
                                         }
                                         {
-                                                auto condExp = node->new_ptr<Exp_t>();
-                                                condExp->pipeExprs.dup(*item.second);
-                                                stack.push_back(condExp);
+                                                stack.push_back(*item.second);
                                         }
-                                        reduce:
+                                        reduce: {
                                                 if (stack.size() == 3) {
-                                                        str_list tmp;
-                                                        auto one = std::get<ast_ptr<false, Exp_t>>(stack.front()).get();
-                                                        transformExp(one, tmp, ExpUsage::Closure);
+                                                        auto condExp = exp->new_ptr<Exp_t>();
+                                                        const auto& one = std::get<ast_list<true, UnaryExp_t>>(stack.front());
+                                                        condExp->pipeExprs.dup(one);
                                                         stack.pop_front();
-                                                        auto two = std::get<std::string>(stack.front());
-                                                        tmp.push_back(two);
+                                                        auto opValue = exp->new_ptr<ExpOpValue_t>();
+                                                        const auto& two = std::get<std::string>(stack.front());
+                                                        auto op = toAst<BinaryOperator_t>(two, exp);
+                                                        opValue->op.set(op);
                                                         stack.pop_front();
-                                                        auto three = std::get<ast_ptr<false, Exp_t>>(stack.front()).get();
-                                                        transformExp(three, tmp, ExpUsage::Closure);
-                                                        conds.push_back(join(tmp, " "sv));
-                                                }
-                                }
-                                auto condStr = join(conds, " and "sv);
-                                if (needWrapping && usage == ExpUsage::Closure) {
-                                        str_list closureLines{anonFuncStart() + nll(exp)};
-                                        closureLines.insert(closureLines.end(), preDefines.begin(), preDefines.end());
-                                        closureLines.push_back(indent() + "return "s + condStr + nll(exp));
-                                        popScope();
-                                        closureLines.push_back(indent() + anonFuncEnd());
-                                        temp.push_back(join(closureLines));
-                                        popAnonVarArg();
-                                        popFunctionScope();
-                                } else {
-                                        temp.push_back(condStr);
-                                        if (!preDefines.empty()) {
-                                                evalLines.insert(evalLines.end(), preDefines.begin(), preDefines.end());
-                                                if (usage == ExpUsage::Assignment) {
-                                                        popScope();
+                                                        const auto& three = std::get<ast_list<true, UnaryExp_t>>(stack.front());
+                                                        opValue->pipeExprs.dup(three);
+                                                        condExp->opValues.push_back(opValue);
+                                                        if (preDefine) {
+                                                                auto ifNode = exp->new_ptr<If_t>();
+                                                                ifNode->type.set(toAst<IfType_t>("unless"sv, exp));
+                                                                auto ifCond = exp->new_ptr<IfCond_t>();
+                                                                ifCond->condition.set(condExp);
+                                                                ifNode->nodes.push_back(ifCond);
+                                                                ifNode->nodes.push_back(toAst<Statement_t>("false"sv, exp));
+                                                                if (newCondExp) {
+                                                                        if (nodes) {
+                                                                                auto block = exp->new_ptr<Block_t>();
+                                                                                auto stmt = exp->new_ptr<Statement_t>();
+                                                                                stmt->content.set(preDefine);
+                                                                                preDefine.set(nullptr);
+                                                                                block->statements.push_back(stmt);
+                                                                                auto simpleValue = exp->new_ptr<SimpleValue_t>();
+                                                                                simpleValue->value.set(ifNode);
+                                                                                auto explist = exp->new_ptr<ExpList_t>();
+                                                                                explist->exprs.push_back(newExp(simpleValue, exp));
+                                                                                auto expListAssign = exp->new_ptr<ExpListAssign_t>();
+                                                                                expListAssign->expList.set(explist);
+                                                                                stmt = exp->new_ptr<Statement_t>();
+                                                                                stmt->content.set(expListAssign);
+                                                                                block->statements.push_back(stmt);
+                                                                                nodes->push_back(block);
+                                                                                nodes = &ifNode->nodes;
+                                                                        } else {
+                                                                                auto ifNodePrev = exp->new_ptr<If_t>();
+                                                                                ifNodePrev->type.set(toAst<IfType_t>("unless"sv, exp));
+                                                                                auto ifCondPrev = exp->new_ptr<IfCond_t>();
+                                                                                ifCondPrev->condition.set(newCondExp);
+                                                                                ifNodePrev->nodes.push_back(ifCondPrev);
+                                                                                ifNodePrev->nodes.push_back(toAst<Statement_t>("false", exp));
+                                                                                auto simpleValue = exp->new_ptr<SimpleValue_t>();
+                                                                                simpleValue->value.set(ifNodePrev);
+                                                                                newCondExp.set(newExp(simpleValue, exp));
+                                                                                nodes = &ifNodePrev->nodes;
+                                                                        }
+                                                                } else {
+                                                                        auto block = exp->new_ptr<Block_t>();
+                                                                        auto stmt = exp->new_ptr<Statement_t>();
+                                                                        stmt->content.set(preDefine);
+                                                                        preDefine.set(nullptr);
+                                                                        block->statements.push_back(stmt);
+                                                                        auto simpleValue = exp->new_ptr<SimpleValue_t>();
+                                                                        simpleValue->value.set(ifNode);
+                                                                        auto explist = exp->new_ptr<ExpList_t>();
+                                                                        explist->exprs.push_back(newExp(simpleValue, exp));
+                                                                        auto expListAssign = exp->new_ptr<ExpListAssign_t>();
+                                                                        expListAssign->expList.set(explist);
+                                                                        stmt = exp->new_ptr<Statement_t>();
+                                                                        stmt->content.set(expListAssign);
+                                                                        block->statements.push_back(stmt);
+                                                                        auto body = exp->new_ptr<Body_t>();
+                                                                        body->content.set(block);
+                                                                        auto doNode = exp->new_ptr<Do_t>();
+                                                                        doNode->body.set(body);
+                                                                        simpleValue = exp->new_ptr<SimpleValue_t>();
+                                                                        simpleValue->value.set(doNode);
+                                                                        newCondExp.set(newExp(simpleValue, exp));
+                                                                        nodes = &ifNode->nodes;
+                                                                }
+                                                        } else {
+                                                                if (newCondExp) {
+                                                                        if (nodes) {
+                                                                                auto explist = exp->new_ptr<ExpList_t>();
+                                                                                explist->exprs.push_back(condExp);
+                                                                                auto expListAssign = exp->new_ptr<ExpListAssign_t>();
+                                                                                expListAssign->expList.set(explist);
+                                                                                auto stmt = exp->new_ptr<Statement_t>();
+                                                                                stmt->content.set(expListAssign);
+                                                                                nodes->push_back(stmt);
+                                                                        } else {
+                                                                                auto opValue = exp->new_ptr<ExpOpValue_t>();
+                                                                                opValue->op.set(toAst<BinaryOperator_t>("and"sv, exp));
+                                                                                opValue->pipeExprs.dup(condExp->pipeExprs);
+                                                                                newCondExp->opValues.push_back(opValue);
+                                                                                newCondExp->opValues.dup(condExp->opValues);
+                                                                        }
+                                                                } else {
+                                                                        newCondExp.set(condExp);
+                                                                }
+                                                        }
                                                 }
                                         }
                                 }
-                        } else {
-                                for (const auto& item : chains) {
-                                        if (!item.first.empty()) {
-                                                temp.push_back(item.first);
-                                        }
-                                        transform_pipe_exp(item.second->objects(), temp, ExpUsage::Closure);
-                                }
+                                popScope();
+                                return newCondExp;
                         }
-                        conditionChainCount = 0;
-                        chains.clear();
+                        return nullptr;
                 };
-                str_list preDefines;
-                for (auto _opValue : exp->opValues.objects()) {
-                        auto opValue = static_cast<ExpOpValue_t*>(_opValue);
+                for (auto opValue_ : exp->opValues.objects()) {
+                        auto opValue = static_cast<ExpOpValue_t*>(opValue_);
                         transformBinaryOperator(opValue->op, temp);
                         auto op = temp.back();
                         temp.pop_back();
@@ -3482,43 +3525,63 @@ private:
                                 conditionChainCount++;
                                 chains.emplace_back(op, &opValue->pipeExprs);
                         } else {
-                                checkChains();
+                                if (auto e = checkChains()) {
+                                        transformExp(e, temp, ExpUsage::Closure);
+                                } else {
+                                        for (const auto& item : chains) {
+                                                if (!item.first.empty()) {
+                                                        temp.push_back(item.first);
+                                                }
+                                                transform_pipe_exp(item.second->objects(), temp, ExpUsage::Closure);
+                                        }
+                                }
+                                chains.clear();
+                                conditionChainCount = 0;
                                 temp.push_back(op);
-                                transform_pipe_exp(opValue->pipeExprs.objects(), temp, ExpUsage::Closure);
+                                chains.emplace_back(Empty, &opValue->pipeExprs);
                         }
                 }
-                checkChains();
-                auto condStr = join(temp, " "sv);
-                switch (usage) {
-                        case ExpUsage::Closure: {
+                if (auto e = checkChains()) {
+                        if (!temp.empty()) {
+                                transformExp(e, temp, ExpUsage::Closure);
+                                auto condStr = join(temp, " "sv);
                                 out.push_back(condStr);
-                                break;
-                        }
-                        case ExpUsage::Assignment: {
-                                auto assignment = exp->new_ptr<ExpListAssign_t>();
-                                assignment->expList.set(assignList);
-                                auto assign = exp->new_ptr<Assign_t>();
-                                assign->values.push_back(toAst<Exp_t>(condStr, exp));
-                                assignment->action.set(assign);
-                                if (evalLines.empty()) {
-                                        transformAssignment(assignment, out);
-                                } else {
-                                        evalLines.push_front(indent() + "do"s + nll(exp));
-                                        evalLines.push_front(getPreDefineLine(assignment));
-                                        pushScope();
-                                        transformAssignment(assignment, evalLines);
-                                        popScope();
-                                        evalLines.push_back(indent() + "end"s + nlr(exp));
-                                        out.push_back(join(evalLines));
+                        } else {
+                                switch (usage) {
+                                        case ExpUsage::Closure:
+                                                transformExp(e, out, ExpUsage::Closure);
+                                                break;
+                                        case ExpUsage::Assignment: {
+                                                auto assignment = exp->new_ptr<ExpListAssign_t>();
+                                                assignment->expList.set(assignList);
+                                                auto assign = exp->new_ptr<Assign_t>();
+                                                assign->values.push_back(e);
+                                                assignment->action.set(assign);
+                                                transformAssignment(assignment, out);
+                                                break;
+                                        }
+                                        case ExpUsage::Return: {
+                                                auto expListLow = exp->new_ptr<ExpListLow_t>();
+                                                expListLow->exprs.push_back(e);
+                                                auto returnNode = exp->new_ptr<Return_t>();
+                                                returnNode->valueList.set(expListLow);
+                                                transformReturn(returnNode, out);
+                                                break;
+                                        }
+                                        default:
+                                                YUEE("invalid expression usage", exp);
+                                                break;
                                 }
-                                break;
                         }
-                        case ExpUsage::Return: {
-                                evalLines.push_back(indent() + "return "s + condStr + nll(exp));
-                                out.push_back(join(evalLines));
-                                break;
+                } else {
+                        for (const auto& item : chains) {
+                                if (!item.first.empty()) {
+                                        temp.push_back(item.first);
+                                }
+                                transform_pipe_exp(item.second->objects(), temp, ExpUsage::Closure);
                         }
-                        default: YUEE("invalid expression usage", exp); break;
+                        auto condStr = join(temp, " "sv);
+                        out.push_back(condStr);
                 }
         }