fix some ambiguous syntax.

1 files changed, 42 insertions, 27 deletions

diff --git a/src/MoonP/moon_parser.cpp b/src/MoonP/moon_parser.cpp
index aafe730..a581e15 100644
--- a/src/MoonP/moon_parser.cpp
+++ b/src/MoonP/moon_parser.cpp
@@ -70,8 +70,13 @@ MoonParser::MoonParser() {
 
         #define sym(str) (Space >> str)
         #define symx(str) expr(str)
-        #define ensure(patt, finally) (((patt) >> (finally)) | ((finally) >> (Cut)))
+        #define ensure(patt, finally) ((patt) >> (finally) | (finally) >> Cut)
         #define key(str) (Space >> 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(patt) (DisableDoChain >> ((patt) >> EnableDoChain | EnableDoChain >> Cut))
+        #define plain_body_with(str) (-key(str) >> InBlock | key(str) >> Statement)
+        #define plain_body (InBlock | Statement)
 
         Variable = pl::user(Name, [](const item_t& item) {
                 State* st = reinterpret_cast<State*>(item.user_data);
@@ -169,7 +174,7 @@ MoonParser::MoonParser() {
                 return true;
         });
 
-        InBlock = Advance >> ensure(Block, PopIndent);
+        InBlock = +SpaceBreak >> Advance >> ensure(Block, PopIndent);
 
         local_flag = expr('*') | expr('^');
         local_values = NameList >> -(sym('=') >> (TableBlock | ExpListLow));
@@ -219,11 +224,11 @@ MoonParser::MoonParser() {
 
         Return = key("return") >> -ExpListLow;
 
-        WithExp = DisableChainBlock >> ensure(ExpList >> -Assign, PopChainBlock);
+        WithExp = ExpList >> -Assign;
 
-        With = key("with") >> -existential_op >> DisableDo >> ensure(WithExp, PopDo) >> -key("do") >> Body;
-        SwitchCase = key("when") >> ExpList >> -key("then") >> Body;
-        SwitchElse = key("else") >> Body;
+        With = key("with") >> -existential_op >> disable_do_chain(WithExp) >> plain_body_with("do");
+        SwitchCase = key("when") >> disable_chain(ExpList) >> plain_body_with("then");
+        SwitchElse = key("else") >> plain_body;
 
         SwitchBlock = *EmptyLine >>
                 Advance >> Seperator >>
@@ -232,31 +237,27 @@ MoonParser::MoonParser() {
                 -(+SpaceBreak >> SwitchElse) >>
                 PopIndent;
 
-        Switch = key("switch") >>
-                DisableDo >> ensure(Exp, PopDo) >>
-                -key("do") >> -Space >> Break >> SwitchBlock;
+        Switch = key("switch") >> disable_do(Exp) >> -key("do")
+                >> -Space >> Break >> SwitchBlock;
 
-        IfCond = Exp >> -Assign;
-        IfElseIf = -(Break >> *EmptyLine >> CheckIndent) >> key("elseif") >> IfCond >> -key("then") >> Body;
-        IfElse = -(Break >> *EmptyLine >> CheckIndent) >> key("else") >> Body;
-        If = key("if") >> Seperator >> IfCond >> -key("then") >> Body >> *IfElseIf >> -IfElse;
-        Unless = key("unless") >> Seperator >> IfCond >> -key("then") >> Body >> *IfElseIf >> -IfElse;
-
-        While = key("while") >> DisableDo >> ensure(Exp, PopDo) >> -key("do") >> Body;
+        IfCond = disable_chain(Exp >> -Assign);
+        IfElseIf = -(Break >> *EmptyLine >> CheckIndent) >> key("elseif") >> IfCond >> plain_body_with("then");
+        IfElse = -(Break >> *EmptyLine >> CheckIndent) >> key("else") >> plain_body;
+        If = key("if") >> Seperator >> IfCond >> plain_body_with("then") >> *IfElseIf >> -IfElse;
+        Unless = key("unless") >> Seperator >> IfCond >> plain_body_with("then") >> *IfElseIf >> -IfElse;
+        
+        While = key("while") >> disable_do_chain(Exp) >> plain_body_with("do");
         Repeat = key("repeat") >> Body >> Break >> *EmptyLine >> CheckIndent >> key("until") >> Exp;
 
         for_step_value = sym(',') >> Exp;
         for_args = Space >> Variable >> sym('=') >> Exp >> sym(',') >> Exp >> -for_step_value;
 
-        For = key("for") >> DisableDo >>
-                ensure(for_args, PopDo) >>
-                -key("do") >> Body;
+        For = key("for") >> disable_do_chain(for_args) >> plain_body_with("do");
 
         for_in = star_exp | ExpList;
 
         ForEach = key("for") >> AssignableNameList >> key("in") >>
-                DisableDo >> ensure(for_in, PopDo) >>
-                -key("do") >> Body;
+                disable_do_chain(for_in) >> plain_body_with("do");
 
         Do = pl::user(key("do"), [](const item_t& item) {
                 State* st = reinterpret_cast<State*>(item.user_data);
@@ -269,12 +270,26 @@ MoonParser::MoonParser() {
                 return true;
         });
 
-        PopDo = pl::user(true_(), [](const item_t& item) {
+        EnableDo = pl::user(true_(), [](const item_t& item) {
                 State* st = reinterpret_cast<State*>(item.user_data);
                 st->doStack.pop();
                 return true;
         });
 
+        DisableDoChain = pl::user(true_(), [](const item_t& item) {
+                State* st = reinterpret_cast<State*>(item.user_data);
+                st->doStack.push(false);
+                st->chainBlockStack.push(false);
+                return true;
+        });
+
+        EnableDoChain = pl::user(true_(), [](const item_t& item) {
+                State* st = reinterpret_cast<State*>(item.user_data);
+                st->doStack.pop();
+                st->chainBlockStack.pop();
+                return true;
+        });
+
         Comprehension = sym('[') >> Exp >> CompInner >> sym(']');
         comp_value = sym(',') >> Exp;
         TblComprehension = sym('{') >> Exp >> -comp_value >> CompInner >> sym('}');
@@ -338,13 +353,13 @@ MoonParser::MoonParser() {
         exp_op_value = Space >> BinaryOperator >> *SpaceBreak >> backcall_exp;
         Exp = Seperator >> backcall_exp >> *exp_op_value;
 
-        DisableChainBlock = pl::user(true_(), [](const item_t& item) {
+        DisableChain = pl::user(true_(), [](const item_t& item) {
                 State* st = reinterpret_cast<State*>(item.user_data);
                 st->chainBlockStack.push(false);
                 return true;
         });
 
-        PopChainBlock = pl::user(true_(), [](const item_t& item) {
+        EnableChain = pl::user(true_(), [](const item_t& item) {
                 State* st = reinterpret_cast<State*>(item.user_data);
                 st->chainBlockStack.pop();
                 return true;
@@ -356,7 +371,7 @@ MoonParser::MoonParser() {
                 return st->chainBlockStack.empty() || st->chainBlockStack.top();
         }) >> +SpaceBreak >> Advance >> ensure(
                 chain_line >> *(+SpaceBreak >> chain_line), PopIndent);
-        ChainValue = Seperator >> (Chain | Callable) >> -existential_op >> (chain_block | -InvokeArgs);
+        ChainValue = Seperator >> (Chain | Callable) >> -existential_op >> -(InvokeArgs | chain_block);
 
         simple_table = Seperator >> KeyValue >> *(sym(',') >> KeyValue);
         Value = SimpleValue | simple_table | ChainValue | String;
@@ -586,10 +601,10 @@ MoonParser::MoonParser() {
         ) >> Space >>
         -statement_appendix >> -statement_sep;
 
-        Body = Space >> Break >> *EmptyLine >> InBlock | Statement;
+        Body = InBlock | Statement;
 
         empty_line_stop = Space >> and_(Stop);
-        Line = CheckIndent >> Statement | and_(Space >> BackcallOperator) >> Advance >> ensure(Statement, PopIndent) | empty_line_stop;
+        Line = and_(check_indent >> Space >> not_(BackcallOperator)) >> Statement | Advance >> ensure(and_(Space >> BackcallOperator) >> Statement, PopIndent) | empty_line_stop;
         Block = Seperator >> Line >> *(+Break >> Line);
 
         Shebang = expr("#!") >> *(not_(Stop) >> Any);