Hide macro replacement

include/cppast/code_generator.hpp

@@ -160,6 +160,7 @@ namespace cppast
             exclude_return, //< Exclude the return type of a function entity.
             exclude_target, //< Exclude the underlying entity of an alias (e.g. typedef).
             declaration,    //< Only write declaration.
+            /// For a macro, it won't show the replacement if this flag is set
             _flag_set_size, //< \exclude
         };
 

src/code_generator.cpp

@@ -92,7 +92,7 @@ namespace
                 output << preprocessor_token("(") << bracket_ws
                        << preprocessor_token(def.parameters().value()) << bracket_ws
                        << preprocessor_token(")");
-            if (!def.replacement().empty())
+            if (!def.replacement().empty() && !output.options().is_set(code_generator::declaration))
                 output << whitespace << preprocessor_token(def.replacement()) << newl;
             else
                 output << newl;

test/code_generator.cpp

@@ -147,7 +147,6 @@ struct foo{
     }
     SECTION("exclude")
     {
-        // exclude all entities starting with `e`
         class exclude_generator : public test_generator
         {
         public:
@@ -157,7 +156,12 @@ struct foo{
             generation_options do_get_options(const cpp_entity& e) override
             {
                 if (e.name().front() == 'e')
+                    // exclude all entities starting with `e`
+                    // add declaration flag to detect check for equality
                     return code_generator::exclude | code_generator::declaration;
+                else if (e.name() == "FOO")
+                    // don't show macro replacement
+                    return code_generator::declaration;
                 return {};
             }
         };
@@ -167,6 +171,8 @@ void e();
 
 void func(int a, int e, int c);
 
+#define FOO hidden
+
 template <typename e1, typename e2>
 void tfunc(int a);
 
@@ -196,6 +202,8 @@ private:
 
         auto synopsis = R"(void func(int a,int c);
 
+#define FOO
+
 void tfunc(int a);
 
 struct base{