Fix #109

peglib.h

@@ -840,6 +840,8 @@ class Context {
 
   std::vector<std::shared_ptr<SemanticValues>> value_stack;
   size_t value_stack_size = 0;
+
+  std::vector<Definition*> rule_stack;
   std::vector<std::vector<std::shared_ptr<Ope>>> args_stack;
 
   bool in_token = false;
@@ -2475,7 +2477,12 @@ inline size_t Holder::parse_core(const char *s, size_t n, SemanticValues &sv,
 
   // Macro reference
   // TODO: need packrat support
-  if (outer_->is_macro) { return ope_->parse(s, n, sv, c, dt); }
+  if (outer_->is_macro) {
+    c.rule_stack.push_back(outer_);
+    auto len = ope_->parse(s, n, sv, c, dt);
+    c.rule_stack.pop_back();
+    return len;
+  }
 
   size_t len;
   any val;
@@ -2491,7 +2498,9 @@ inline size_t Holder::parse_core(const char *s, size_t n, SemanticValues &sv,
 
     auto &chldsv = c.push();
 
+    c.rule_stack.push_back(outer_);
     len = ope_->parse(s, n, chldsv, c, dt);
+    c.rule_stack.pop_back();
 
     // Invoke action
     if (success(len)) {
@@ -2556,7 +2565,7 @@ inline size_t Reference::parse_core(const char *s, size_t n, SemanticValues &sv,
     // Reference rule
     if (rule_->is_macro) {
       // Macro
-      FindReference vis(c.top_args(), rule_->params);
+      FindReference vis(c.top_args(), c.rule_stack.back()->params);
 
       // Collect arguments
       std::vector<std::shared_ptr<Ope>> args;
@@ -2571,6 +2580,8 @@ inline size_t Reference::parse_core(const char *s, size_t n, SemanticValues &sv,
       return ope->parse(s, n, sv, c, dt);
     } else {
       // Definition
+      c.push_args(std::vector<std::shared_ptr<Ope>>());
+      auto se = make_scope_exit([&]() { c.pop_args(); });
       auto ope = get_core_operator();
       return ope->parse(s, n, sv, c, dt);
     }

test/test2.cc

@@ -903,20 +903,40 @@ TEST_CASE("Macro token check test", "[macro]")
     REQUIRE(parser["T"].is_token() == true);
 }
 
-TEST_CASE("Macro rule-parameter collision", "[macro]")
-{
-    parser parser(R"(
+TEST_CASE("Macro passes an arg to another macro", "[macro]") {
+  parser parser(R"(
         A    <- B(C)
         B(D) <- D
         C    <- 'c'
         D    <- 'd'
 	)");
 
-    REQUIRE(parser.parse("c"));
+  REQUIRE(parser.parse("c"));
+}
+
+TEST_CASE("Nested macro call", "[macro]") {
+  parser parser(R"(
+        A    <- B(T)
+        B(X) <- C(X)
+        C(Y) <- Y
+        T    <- 'val'
+	)");
+
+  REQUIRE(parser.parse("val"));
 }
 
-TEST_CASE("Line information test", "[line information]")
+TEST_CASE("Nested macro call2", "[macro]")
 {
+    parser parser(R"(
+        START           <- A('TestVal1', 'TestVal2')+
+        A(Aarg1, Aarg2) <- B(Aarg1) '#End'
+        B(Barg1)        <- '#' Barg1
+	)");
+
+    REQUIRE(parser.parse("#TestVal1#End"));
+}
+
+TEST_CASE("Line information test", "[line information]") {
     parser parser(R"(
         S    <- _ (WORD _)+
         WORD <- [A-Za-z]+