1 files changed, 33 insertions, 10 deletions

diff --git a/src/yuescript/yue_parser.cpp b/src/yuescript/yue_parser.cpp
index 1b72a8c..1999721 100644
--- a/src/yuescript/yue_parser.cpp
+++ b/src/yuescript/yue_parser.cpp
@@ -50,6 +50,15 @@ public:
                 } \
         } while (false)
 
+#define RaiseErrorI(msg, item) \
+        do { \
+                if (reinterpret_cast<State*>(item.user_data)->lax) { \
+                        return -1; \
+                } else { \
+                        throw ParserError(msg, item.begin); \
+                } \
+        } while (false)
+
 // clang-format off
 YueParser::YueParser() {
         plain_space = *set(" \t");
@@ -316,14 +325,14 @@ YueParser::YueParser() {
                         for (input_it i = item.begin->m_it; i != item.end->m_it; ++i) {
                                 switch (*i) {
                                         case '\t': indent += 4; break;
-                                        default: RaiseError("can not mix the use of tabs and spaces as indents"sv, item); break;
+                                        default: RaiseErrorI("can not mix the use of tabs and spaces as indents"sv, item); break;
                                 }
                         }
                 } else {
                         for (input_it i = item.begin->m_it; i != item.end->m_it; ++i) {
                                 switch (*i) {
                                         case ' ': indent++; break;
-                                        default: RaiseError("can not mix the use of tabs and spaces as indents"sv, item); break;
+                                        default: RaiseErrorI("can not mix the use of tabs and spaces as indents"sv, item); break;
                                 }
                         }
                 }
@@ -357,6 +366,12 @@ YueParser::YueParser() {
                         }
                 }
                 State* st = reinterpret_cast<State*>(item.user_data);
+                if (st->indents.empty()) {
+                        RaiseError("unknown indent level"sv, item);
+                }
+                if (st->indents.top() > indent) {
+                        RaiseError("unexpected dedent"sv, item);
+                }
                 st->indents.push(indent);
                 return true;
         });
@@ -1014,16 +1029,24 @@ YueParser::YueParser() {
 
         FnArgDef = (Variable | SelfItem >> -ExistentialOp) >> -(space >> '`' >> space >> Name) >> -(space >> '=' >> space >> Exp) | TableLit | SimpleTable;
 
-        check_vararg_position = and_(white >> ')') | white >> -(',' >> white) >> vararg_position_error;
+        check_vararg_position = and_(white >> (')' | key("using"))) | white >> -(',' >> white) >> vararg_position_error;
 
-        FnArgDefList = Seperator >> (
-                fn_arg_def_lit_lines >> -(-(space >> ',') >> white >> VarArg >> -(space >> '`' >> space >> Name) >> check_vararg_position) |
-                white >> VarArg >> -(space >> '`' >> space >> Name) >> check_vararg_position
-        );
+        var_arg_def = (
+                VarArg |
+                +space_break >> push_indent_match >> ensure(space >> VarArg >> -(space >> '`' >> space >> Name), pop_indent)
+        ) >> check_vararg_position;
+
+        FnArgDefList = Seperator >>
+                -fn_arg_def_list >>
+                -(-(space >> ',') >> +space_break >> fn_arg_def_lit_lines) >>
+                -(-(space >> ',') >> space >> var_arg_def);
 
         OuterVarShadow = key("using") >> space >> (key("nil") | NameList);
 
-        FnArgsDef = '(' >> *space_break >> -FnArgDefList >> -(white >> OuterVarShadow) >> white >> -(and_(',') >> unexpected_comma_error) >> ')';
+        outer_var_shadow_def = OuterVarShadow |
+                +space_break >> push_indent_match >> ensure(space >> OuterVarShadow, pop_indent);
+
+        FnArgsDef = '(' >> space >> -FnArgDefList >> -(space >> outer_var_shadow_def) >> white >> -(and_(',') >> unexpected_comma_error) >> ')';
         FnArrow = expr("->") | "=>";
         FunLit = pl::user(true_(), [](const item_t& item) {
                 State* st = reinterpret_cast<State*>(item.user_data);
@@ -1035,11 +1058,11 @@ YueParser::YueParser() {
         ) >> space >> FnArrow >> -(space >> Body);
 
         MacroName = '$' >> UnicodeName;
-        macro_args_def = '(' >> white >> -FnArgDefList >> white >> -(and_(',') >> unexpected_comma_error) >> ')';
+        macro_args_def = '(' >> space >> -FnArgDefList >> white >> -(and_(',') >> unexpected_comma_error) >> ')';
         MacroLit = -(macro_args_def >> space) >> "->" >> space >> Body;
         MacroFunc = MacroName >> (Invoke | InvokeArgs);
         Macro = key("macro") >> space >> (
-                UnicodeName >> space >> '=' >> space >> (MacroLit | MacroFunc | expected_expression_error) |
+                UnicodeName >> space >> '=' >> space >> (MacroLit | MacroFunc | invalid_macro_definition_error) |
                 invalid_macro_definition_error
         );
         MacroInPlace = '$' >> space >> "->" >> space >> Body;