more optimization for parser.

2 files changed, 105 insertions, 93 deletions

diff --git a/src/yuescript/yue_parser.cpp b/src/yuescript/yue_parser.cpp
index e8b47b7..e3d6b07 100644
--- a/src/yuescript/yue_parser.cpp
+++ b/src/yuescript/yue_parser.cpp
@@ -44,17 +44,17 @@ YueParser::YueParser() {
         MultiLineComment = multi_line_open >> multi_line_content >> multi_line_close;
         EscapeNewLine = expr('\\') >> *(set(" \t") | MultiLineComment) >> -Comment >> Break;
         space_one = set(" \t") | and_(set("-\\")) >> (MultiLineComment | EscapeNewLine);
-        Space = *space_one >> -Comment;
+        Space = -(and_(set(" \t-\\")) >> *space_one >> -Comment);
         SpaceBreak = Space >> Break;
         White = Space >> *(Break >> Space);
         EmptyLine = SpaceBreak;
-        AlphaNum = range('a', 'z') | range('A', 'Z') | range('0', '9') | '_';
-        Name = (range('a', 'z') | range('A', 'Z') | '_') >> *AlphaNum;
+        AlphaNum = sel({range('a', 'z'), range('A', 'Z'), range('0', '9'), expr('_')});
+        Name = sel({range('a', 'z'), range('A', 'Z'), expr('_')}) >> *AlphaNum;
         num_expo = set("eE") >> -set("+-") >> num_char;
         num_expo_hex = set("pP") >> -set("+-") >> num_char;
         lj_num = -set("uU") >> set("lL") >> set("lL");
         num_char = range('0', '9') >> *(range('0', '9') | expr('_') >> and_(range('0', '9')));
-        num_char_hex = range('0', '9') | range('a', 'f') | range('A', 'F');
+        num_char_hex = sel({range('0', '9'), range('a', 'f'), range('A', 'F')});
         num_lit = num_char_hex >> *(num_char_hex | expr('_') >> and_(num_char_hex));
         Num = sel({
                 expr("0x") >> (
@@ -84,16 +84,15 @@ YueParser::YueParser() {
                 return false;
         });
 
-        #define sym(str) (Space >> str)
         #define ensure(patt, finally) ((patt) >> (finally) | (finally) >> Cut)
         #define key(str) (str >> not_(AlphaNum))
         #define disable_do(patt) (DisableDo >> ((patt) >> EnableDo | EnableDo >> Cut))
         #define disable_chain(patt) (DisableChain >> ((patt) >> EnableChain | EnableChain >> Cut))
         #define disable_do_chain_arg_table_block(patt) (DisableDoChainArgTableBlock >> ((patt) >> EnableDoChainArgTableBlock | EnableDoChainArgTableBlock >> Cut))
         #define disable_arg_table_block(patt) (DisableArgTableBlock >> ((patt) >> EnableArgTableBlock | EnableArgTableBlock >> Cut))
-        #define body_with(str) (Space >> (key(str) >> Space >> (InBlock | Statement) | InBlock | empty_block_error))
+        #define body_with(str) (Space >> sel({key(str) >> Space >> (InBlock | Statement), InBlock, empty_block_error}))
         #define opt_body_with(str) (Space >> (key(str) >> Space >> (InBlock | Statement) | InBlock))
-        #define body (Space >> (InBlock | Statement | empty_block_error))
+        #define body (Space >> sel({InBlock, Statement, empty_block_error}))
 
         Variable = pl::user(Name, [](const item_t& item) {
                 State* st = reinterpret_cast<State*>(item.user_data);
@@ -194,53 +193,53 @@ YueParser::YueParser() {
         InBlock = Space >> +(plain_space >> Break) >> Advance >> ensure(Block, PopIndent);
 
         local_flag = expr('*') | expr('^');
-        local_values = NameList >> -(sym('=') >> (TableBlock | ExpListLow));
+        local_values = NameList >> -(Space >> expr('=') >> (TableBlock | ExpListLow));
         Local = key("local") >> (Space >> local_flag | local_values);
 
         const_attrib = key("const");
         close_attrib = key("close");
-        local_const_item = (Space >> Variable | simple_table | TableLit);
+        local_const_item = sel({Space >> Variable, simple_table, TableLit});
         LocalAttrib = (
-                const_attrib >> Seperator >> local_const_item >> *(sym(',') >> local_const_item) |
-                close_attrib >> Seperator >> Space >> Variable >> *(sym(',') >> Space >> Variable)
+                const_attrib >> Seperator >> local_const_item >> *(Space >> expr(',') >> local_const_item) |
+                close_attrib >> Seperator >> Space >> Variable >> *(Space >> expr(',') >> Space >> Variable)
         ) >> Assign;
 
-        colon_import_name = sym('\\') >> Space >> Variable;
+        colon_import_name = Space >> expr('\\') >> Space >> Variable;
         ImportName = colon_import_name | Space >> Variable;
-        ImportNameList = Seperator >> *SpaceBreak >> ImportName >> *((+SpaceBreak | sym(',') >> *SpaceBreak) >> ImportName);
+        ImportNameList = Seperator >> *SpaceBreak >> ImportName >> *((+SpaceBreak | Space >> expr(',') >> *SpaceBreak) >> ImportName);
         ImportFrom = ImportNameList >> *SpaceBreak >> Space >> key("from") >> Exp;
 
         import_literal_inner = (range('a', 'z') | range('A', 'Z') | set("_-")) >> *(AlphaNum | '-');
         import_literal_chain = Seperator >> import_literal_inner >> *(expr('.') >> import_literal_inner);
-        ImportLiteral = sym('\'') >> import_literal_chain >> expr('\'') | sym('"') >> import_literal_chain >> expr('"');
+        ImportLiteral = Space >> expr('\'') >> import_literal_chain >> expr('\'') | Space >> expr('"') >> import_literal_chain >> expr('"');
 
         macro_name_pair = Space >> MacroName >> Space >> expr(':') >> Space >> MacroName;
         import_all_macro = expr('$');
         ImportTabItem = sel({
                 variable_pair,
                 normal_pair,
-                sym(':') >> MacroName,
+                Space >> expr(':') >> MacroName,
                 macro_name_pair,
                 Space >> import_all_macro,
                 meta_variable_pair,
                 meta_normal_pair,
                 Exp
         });
-        ImportTabList = ImportTabItem >> *(sym(',') >> ImportTabItem);
+        ImportTabList = ImportTabItem >> *(Space >> expr(',') >> ImportTabItem);
         ImportTabLine = (
                 PushIndent >> (ImportTabList >> PopIndent | PopIndent)
         ) | Space;
-        import_tab_lines = SpaceBreak >> ImportTabLine >> *(-sym(',') >> SpaceBreak >> ImportTabLine) >> -sym(',');
+        import_tab_lines = SpaceBreak >> ImportTabLine >> *(-(Space >> expr(',')) >> SpaceBreak >> ImportTabLine) >> -(Space >> expr(','));
         ImportTabLit = seq({
                 Seperator,
-                sym('{'),
+                Space, expr('{'),
                 -ImportTabList,
-                -sym(','),
+                -(Space >> expr(',')),
                 -import_tab_lines,
                 White,
-                sym('}')
+                expr('}')
         }) | seq({
-                Seperator, KeyValue, *(sym(',') >> KeyValue)
+                Seperator, KeyValue, *(Space >> expr(',') >> KeyValue)
         });
 
         ImportAs = ImportLiteral >> -(Space >> key("as") >> Space >> (ImportTabLit | Variable | import_all_macro));
@@ -269,7 +268,10 @@ YueParser::YueParser() {
 
         exp_not_tab = not_(simple_table | TableLit) >> Exp;
 
-        SwitchList = Seperator >> (and_(simple_table | TableLit) >> Exp | exp_not_tab >> *(sym(',') >> exp_not_tab));
+        SwitchList = Seperator >> (
+                and_(simple_table | TableLit) >> Exp |
+                exp_not_tab >> *(Space >> expr(',') >> exp_not_tab)
+        );
         Switch = Space >> key("switch") >> Exp >>
                 Seperator >> (
                         SwitchCase >> Space >> (
@@ -290,8 +292,8 @@ YueParser::YueParser() {
         While = WhileType >> disable_do_chain_arg_table_block(Exp) >> opt_body_with("do");
         Repeat = seq({key("repeat"), Body, Break, *EmptyLine, CheckIndent, Space, key("until"), Exp});
 
-        for_step_value = sym(',') >> Exp;
-        for_args = Space >> Variable >> sym('=') >> Exp >> sym(',') >> Exp >> -for_step_value;
+        for_step_value = Space >> expr(',') >> Exp;
+        for_args = Space >> Variable >> Space >> expr('=') >> Exp >> Space >> expr(',') >> Exp >> -for_step_value;
 
         For = key("for") >> disable_do_chain_arg_table_block(for_args) >> opt_body_with("do");
 
@@ -348,17 +350,17 @@ YueParser::YueParser() {
         catch_block = Break >> *EmptyLine >> CheckIndent >> Space >> key("catch") >> Space >> Variable >> InBlock;
         Try = Space >> key("try") >> (InBlock | Exp) >> -catch_block;
 
-        Comprehension = sym('[') >> not_('[') >> Exp >> Space >> CompInner >> sym(']');
-        comp_value = sym(',') >> Exp;
-        TblComprehension = sym('{') >> Exp >> -comp_value >> Space >> CompInner >> sym('}');
+        Comprehension = Space >> expr('[') >> not_('[') >> Exp >> Space >> CompInner >> Space >> expr(']');
+        comp_value = Space >> expr(',') >> Exp;
+        TblComprehension = Space >> expr('{') >> Exp >> -comp_value >> Space >> CompInner >> Space >> expr('}');
 
         CompInner = Seperator >> (CompForEach | CompFor) >> *CompClause;
-        star_exp = sym('*') >> Exp;
+        star_exp = Space >> expr('*') >> Exp;
         CompForEach = key("for") >> AssignableNameList >> Space >> key("in") >> (star_exp | Exp);
-        CompFor = key("for") >> Space >> Variable >> sym('=') >> Exp >> sym(',') >> Exp >> -for_step_value;
-        CompClause = Space >> (CompFor | CompForEach | key("when") >> Exp);
+        CompFor = key("for") >> Space >> Variable >> Space >> expr('=') >> Exp >> Space >> expr(',') >> Exp >> -for_step_value;
+        CompClause = Space >> sel({CompFor, CompForEach, key("when") >> Exp});
 
-        Assign = sym('=') >> Seperator >> sel({
+        Assign = Space >> expr('=') >> Seperator >> sel({
                 With, If, Switch, TableBlock,
                 Exp >> *(Space >> set(",;") >> Exp)
         });
@@ -376,7 +378,7 @@ YueParser::YueParser() {
 
         Update = Space >> update_op >> expr("=") >> Exp;
 
-        Assignable = Space >> (AssignableChain | Variable | SelfName);
+        Assignable = Space >> sel({AssignableChain, Variable, SelfName});
 
         unary_value = +(unary_operator >> Space) >> Value;
 
@@ -439,12 +441,12 @@ YueParser::YueParser() {
                 -table_appending_op
         });
 
-        simple_table = seq({Seperator, KeyValue, *(sym(',') >> KeyValue)});
+        simple_table = seq({Seperator, KeyValue, *(Space >> expr(',') >> KeyValue)});
         Value = sel({SimpleValue, simple_table, ChainValue, String});
 
         single_string_inner = expr('\\') >> set("'\\") | not_(expr('\'')) >> Any;
         SingleString = expr('\'') >> *single_string_inner >> expr('\'');
-        interp = expr("#{") >> Exp >> sym('}');
+        interp = expr("#{") >> Exp >> Space >> expr('}');
         double_string_plain = expr('\\') >> set("\"\\") | not_(expr('"')) >> Any;
         double_string_inner = +(not_(interp) >> double_string_plain);
         double_string_content = double_string_inner | interp;
@@ -521,8 +523,8 @@ YueParser::YueParser() {
                 Slice,
                 Index >> -existential_op
         });
-        DotChainItem = expr('.') >> (Name | Metatable | Metamethod);
-        ColonChainItem = (expr('\\') | expr("::")) >> (LuaKeyword | Name | Metamethod);
+        DotChainItem = expr('.') >> sel({Name, Metatable, Metamethod});
+        ColonChainItem = (expr('\\') | expr("::")) >> sel({LuaKeyword, Name, Metamethod});
         invoke_chain = Invoke >> -existential_op >> -ChainItems;
         ColonChain = ColonChainItem >> -existential_op >> -invoke_chain;
 
@@ -544,7 +546,7 @@ YueParser::YueParser() {
                 and_(expr('{')) >> TableLit
         });
 
-        SpreadExp = sym("...") >> Exp;
+        SpreadExp = Space >> expr("...") >> Exp;
 
         TableValue = sel({
                 variable_pair_def,
@@ -555,17 +557,17 @@ YueParser::YueParser() {
                 normal_def
         });
 
-        table_lit_lines = SpaceBreak >> TableLitLine >> *(-sym(',') >> SpaceBreak >> TableLitLine) >> -sym(',');
+        table_lit_lines = SpaceBreak >> TableLitLine >> *(-(Space >> expr(',')) >> SpaceBreak >> TableLitLine) >> -(Space >> expr(','));
 
         TableLit = seq({
-                sym('{'), Seperator,
+                Space, expr('{'), Seperator,
                 -TableValueList,
-                -sym(','),
+                -(Space >> expr(',')),
                 -table_lit_lines,
-                White, sym('}')
+                White, expr('}')
         });
 
-        TableValueList = TableValue >> *(sym(',') >> TableValue);
+        TableValueList = TableValue >> *(Space >> expr(',') >> TableValue);
 
         TableLitLine = (
                 PushIndent >> (TableValueList >> PopIndent | PopIndent)
@@ -575,24 +577,27 @@ YueParser::YueParser() {
 
         TableBlockInner = Seperator >> KeyValueLine >> *(+SpaceBreak >> KeyValueLine);
         TableBlock = +SpaceBreak >> Advance >> ensure(TableBlockInner, PopIndent);
-        TableBlockIndent = sym('*') >> Seperator >> disable_arg_table_block(
-                KeyValueList >> -sym(',') >>
-                -(+SpaceBreak >> Advance >> ensure(KeyValueList >> -sym(',') >> *(+SpaceBreak >> KeyValueLine), PopIndent)));
-
-        class_member_list = Seperator >> KeyValue >> *(sym(',') >> KeyValue);
-        ClassLine = CheckIndent >> (class_member_list | Space >> Statement) >> -sym(',');
-        ClassBlock = +SpaceBreak >> Advance >> Seperator >> ClassLine >> *(+SpaceBreak >> ClassLine) >> PopIndent;
-
-        ClassDecl =
-                Space >> key("class") >> not_(expr(':')) >> disable_arg_table_block(
-                        -Assignable >>
-                        -(Space >> key("extends") >> PreventIndent >> ensure(Exp, PopIndent)) >>
-                        -(Space >> key("using") >> PreventIndent >> ensure(ExpList, PopIndent))
-                ) >> -ClassBlock;
-
-        global_values = NameList >> -(sym('=') >> (TableBlock | ExpListLow));
+        TableBlockIndent = Space >> expr('*') >> Seperator >> disable_arg_table_block(
+                KeyValueList >> -(Space >> expr(',')) >>
+                -(+SpaceBreak >> Advance >> ensure(KeyValueList >> -(Space >> expr(',')) >> *(+SpaceBreak >> KeyValueLine), PopIndent)));
+
+        class_member_list = Seperator >> KeyValue >> *(Space >> expr(',') >> KeyValue);
+        ClassLine = CheckIndent >> (class_member_list | Space >> Statement) >> -(Space >> expr(','));
+        ClassBlock = seq({+SpaceBreak, Advance, Seperator, ClassLine, *(+SpaceBreak >> ClassLine), PopIndent});
+
+        ClassDecl = seq({
+                Space, key("class"), not_(expr(':')),
+                disable_arg_table_block(seq({
+                        -Assignable,
+                        -seq({Space, key("extends"), PreventIndent, ensure(Exp, PopIndent)}),
+                        -seq({Space, key("using"), PreventIndent, ensure(ExpList, PopIndent)})
+                })),
+                -ClassBlock
+        });
+
+        global_values = NameList >> -(Space >> expr('=') >> (TableBlock | ExpListLow));
         global_op = expr('*') | expr('^');
-        Global = key("global") >> (ClassDecl | (Space >> global_op) | global_values);
+        Global = key("global") >> sel({ClassDecl, Space >> global_op, global_values});
 
         export_default = key("default");
 
@@ -624,29 +629,30 @@ YueParser::YueParser() {
                 return true;
         })) >> not_(Space >> statement_appendix);
 
-        variable_pair = sym(':') >> Variable;
+        variable_pair = Space >> expr(':') >> Variable;
 
         normal_pair = seq({
                 Space,
                 sel({
                         KeyName,
-                        seq({expr('['), not_('['), Exp, sym(']')}),
+                        seq({expr('['), not_('['), Exp, Space >> expr(']')}),
                         String
                 }),
                 expr(':'), not_(':'),
                 sel({Exp, TableBlock, +SpaceBreak >> Exp})
         });
 
-        meta_variable_pair = sym(":<") >> Space >> Variable >> sym('>');
+        meta_variable_pair = Space >> expr(":<") >> Space >> Variable >> Space >> expr('>');
 
-        meta_normal_pair = sym('<') >> Space >> -meta_index >> sym(">:") >>
-                (Exp | TableBlock | +(SpaceBreak) >> Exp);
+        meta_normal_pair = Space >> expr('<') >> Space >> -meta_index >> Space >> expr(">:") >>
+                sel({Exp, TableBlock, +(SpaceBreak) >> Exp});
 
-        variable_pair_def = variable_pair >> -(sym('=') >> Exp);
-        normal_pair_def = normal_pair >> -(sym('=') >> Exp);
-        meta_variable_pair_def = meta_variable_pair >> -(sym('=') >> Exp);
-        meta_normal_pair_def = meta_normal_pair >> -(sym('=') >> Exp);
-        normal_def = Exp >> Seperator >> -(sym('=') >> Exp);
+        destruct_def = -seq({Space, expr('='), Exp});
+        variable_pair_def = variable_pair >> destruct_def;
+        normal_pair_def = normal_pair >> destruct_def;
+        meta_variable_pair_def = meta_variable_pair >> destruct_def;
+        meta_normal_pair_def = meta_normal_pair >> destruct_def;
+        normal_def = Exp >> Seperator >> destruct_def;
 
         KeyValue = sel({
                 variable_pair,
@@ -654,16 +660,20 @@ YueParser::YueParser() {
                 meta_variable_pair,
                 meta_normal_pair
         });
-        KeyValueList = KeyValue >> *(sym(',') >> KeyValue);
-        KeyValueLine = CheckIndent >> (KeyValueList >> -sym(',') | TableBlockIndent | Space >> expr('*') >> (SpreadExp | Exp | TableBlock));
+        KeyValueList = KeyValue >> *(Space >> expr(',') >> KeyValue);
+        KeyValueLine = CheckIndent >> sel({
+                KeyValueList >> -(Space >> expr(',')),
+                TableBlockIndent,
+                Space >> expr('*') >> sel({SpreadExp, Exp, TableBlock})
+        });
 
-        FnArgDef = (Variable | SelfName >> -existential_op) >> -(sym('=') >> Space >> Exp);
+        FnArgDef = (Variable | SelfName >> -existential_op) >> -(Space >> expr('=') >> Space >> Exp);
 
         FnArgDefList = Space >> Seperator >> (
                 seq({
                         FnArgDef,
-                        *seq({(sym(',') | Break), White, FnArgDef}),
-                        -seq({(sym(',') | Break), White, VarArg})
+                        *seq({(Space >> expr(',') | Break), White, FnArgDef}),
+                        -seq({(Space >> expr(',') | Break), White, VarArg})
                 }) |
                         VarArg
         );
@@ -675,14 +685,14 @@ YueParser::YueParser() {
         FunLit = seq({-FnArgsDef, Space, fn_arrow, -Body});
 
         MacroName = expr('$') >> Name;
-        macro_args_def = sym('(') >> White >> -FnArgDefList >> White >> sym(')');
+        macro_args_def = Space >> expr('(') >> White >> -FnArgDefList >> White >> Space >> expr(')');
         MacroLit = -macro_args_def >> Space >> expr("->") >> Body;
-        Macro = key("macro") >> Space >> Name >> sym('=') >> MacroLit;
+        Macro = key("macro") >> Space >> Name >> Space >> expr('=') >> MacroLit;
         MacroInPlace = expr('$') >> Space >> expr("->") >> Body;
 
-        NameList = Seperator >> Space >> Variable >> *(sym(',') >> Space >> Variable);
+        NameList = Seperator >> Space >> Variable >> *(Space >> expr(',') >> Space >> Variable);
         NameOrDestructure = Space >> Variable | TableLit;
-        AssignableNameList = Seperator >> NameOrDestructure >> *(sym(',') >> NameOrDestructure);
+        AssignableNameList = Seperator >> NameOrDestructure >> *(Space >> expr(',') >> NameOrDestructure);
 
         fn_arrow_back = expr('<') >> set("-=");
         Backcall = seq({-FnArgsDef, Space, fn_arrow_back, Space, ChainValue});
@@ -694,11 +704,11 @@ YueParser::YueParser() {
                 *seq({+SpaceBreak, CheckIndent, Space, PipeOperator, unary_exp})
         });
 
-        ExpList = Seperator >> Exp >> *(sym(',') >> Exp);
+        ExpList = Seperator >> Exp >> *(Space >> expr(',') >> Exp);
         ExpListLow = Seperator >> Exp >> *(Space >> set(",;") >> Exp);
 
-        ArgLine = CheckIndent >> Exp >> *(sym(',') >> Exp);
-        ArgBlock = ArgLine >> *(sym(',') >> SpaceBreak >> ArgLine) >> PopIndent;
+        ArgLine = CheckIndent >> Exp >> *(Space >> expr(',') >> Exp);
+        ArgBlock = ArgLine >> *(Space >> expr(',') >> SpaceBreak >> ArgLine) >> PopIndent;
 
         arg_table_block = pl::user(true_(), [](const item_t& item) {
                 State* st = reinterpret_cast<State*>(item.user_data);
@@ -706,23 +716,23 @@ YueParser::YueParser() {
         }) >> TableBlock;
 
         invoke_args_with_table =
-                sym(',') >> (
+                Space >> expr(',') >> (
                         TableBlock |
                         SpaceBreak >> Advance >> ArgBlock >> -arg_table_block
                 ) | arg_table_block;
 
-        leading_spaces_error = pl::user(+space_one >> expr('(') >> Exp >> +(sym(',') >> Exp) >> sym(')'), [](const item_t& item) {
+        leading_spaces_error = pl::user(+space_one >> expr('(') >> Exp >> +(Space >> expr(',') >> Exp) >> Space >> expr(')'), [](const item_t& item) {
                 throw ParserError("write invoke arguments in parentheses without leading spaces or just leading spaces without parentheses", *item.begin, *item.end);
                 return false;
         });
 
         InvokeArgs =
                 not_(set("-~")) >> Seperator >>
-                (
-                        (Exp >> *(sym(',') >> Exp) >> -invoke_args_with_table) |
-                        arg_table_block |
+                sel({
+                        Exp >> *(Space >> expr(',') >> Exp) >> -invoke_args_with_table,
+                        arg_table_block,
                         leading_spaces_error
-                );
+                });
 
         const_value = sel({expr("nil"), expr("true"), expr("false")}) >> not_(AlphaNum);
 
@@ -744,9 +754,9 @@ YueParser::YueParser() {
         yue_multiline_comment = multi_line_open >> YueMultilineComment >> multi_line_close;
         yue_comment = check_indent >> (yue_multiline_comment >> *(set(" \t") | yue_multiline_comment) >> -yue_line_comment | yue_line_comment) >> and_(Break);
 
-        ChainAssign = Seperator >> Exp >> +(sym('=') >> Exp >> Space >> and_('=')) >> Assign;
+        ChainAssign = Seperator >> Exp >> +(Space >> expr('=') >> Exp >> Space >> and_('=')) >> Assign;
 
-        statement_appendix = (if_line | while_line | CompInner) >> Space;
+        statement_appendix = sel({if_line, while_line, CompInner}) >> Space;
         statement_sep = and_(seq({
                 *SpaceBreak, CheckIndent, Space,
                 sel({
@@ -778,10 +788,11 @@ YueParser::YueParser() {
 
         Body = InBlock | Space >> Statement;
 
-        empty_line_break = (
-                check_indent >> (MultiLineComment >> Space | Comment) |
-                advance >> ensure(MultiLineComment >> Space | Comment, PopIndent) |
-                plain_space) >> and_(Break);
+        empty_line_break = sel({
+                check_indent >> (MultiLineComment >> Space | Comment),
+                advance >> ensure(MultiLineComment >> Space | Comment, PopIndent),
+                plain_space
+        }) >> and_(Break);
 
         indentation_error = pl::user(not_(PipeOperator | eof()), [](const item_t& item) {
                 throw ParserError("unexpected indent", *item.begin, *item.end);
diff --git a/src/yuescript/yue_parser.h b/src/yuescript/yue_parser.h
index 1068468..0e87a71 100644
--- a/src/yuescript/yue_parser.h
+++ b/src/yuescript/yue_parser.h
@@ -185,6 +185,7 @@ private:
         rule lua_string_close;
         rule FnArgsExpList;
         rule FnArgs;
+        rule destruct_def;
         rule macro_args_def;
         rule chain_call;
         rule chain_call_list;