fix(cpp1): define static data member with placeholder type in class

Author: JohelEGP

regression-tests/pure2-type-and-namespace-aliases.cpp2

@@ -38,16 +38,12 @@ myclass5: type == myclass4;
 
 myclass3: @struct type = {
     v0 :== :std::array = (0);;
-    v1: std::array == v0;
-    v2: myclass3 == :myclass3 = ();;
+    v1 :== v0; // OK: Also uses the Cpp2 placeholder type.
+    v2: myclass3 == myclass3(); // OK: Doesn't use the Cpp2 placeholder type.
     v3: _ == v0;
-    // v4 :== v2; // Not (yet) supported.
-    // v5: myclass4 == :myclass4 = ();; // Not yet supported.
-    // v6: myclass5 == :myclass5 = ();; // Not yet supported.
-    // v7 :== myclass3(); // Not (yet) supported.
-
-    // There's also a false positive:
-    // <https://github.com/hsutter/cppfront/issues/666#issuecomment-1722329609>.
+    v4: myclass3 == v2; // OK: Doesn't use the Cpp2 placeholder type.
+    v5: myclass4 == myclass4(); // OK: Doesn't use the Cpp2 placeholder type.
+    v6: myclass5 == myclass5(); // OK: Doesn't use the Cpp2 placeholder type.
 }
 
 myclass4: @struct type = { }

regression-tests/test-results/pure2-print.cpp

@@ -22,7 +22,7 @@ class outer {
     public: template<typename T> 
 CPP2_REQUIRES_ (true)
 #line 6 "pure2-print.cpp2"
-    static constexpr T object_alias = 42;
+    static const T object_alias;
 
     public: class mytype final
      {
@@ -90,6 +90,12 @@ auto main() -> int;
 //=== Cpp2 function definitions =================================================
 
 
+#line 6 "pure2-print.cpp2"
+    template<typename T> 
+requires (true)
+#line 6 "pure2-print.cpp2"
+    inline CPP2_CONSTEXPR T outer::object_alias = 42;
+
 #line 10 "pure2-print.cpp2"
         [[nodiscard]] auto outer::mytype::f() -> int { return 42;  }
 

regression-tests/test-results/pure2-type-and-namespace-aliases.cpp

@@ -24,7 +24,7 @@ template<typename T> class myclass2;
 class myclass3;
 
 
-#line 53 "pure2-type-and-namespace-aliases.cpp2"
+#line 49 "pure2-type-and-namespace-aliases.cpp2"
 class myclass4;
 
 template<typename T> class myclass6;
@@ -59,7 +59,7 @@ auto myfunc() -> void;
 
 #line 25 "pure2-type-and-namespace-aliases.cpp2"
 template<typename T> class myclass2 {
-    public: static constexpr int value = 42;
+    public: static const int value;
 
     public: myclass2() = default;
     public: myclass2(myclass2 const&) = delete; /* No 'that' constructor, suppress copy */
@@ -75,24 +75,20 @@ using myclass5 = myclass4;
 
 class myclass3 {
     public: static constexpr auto v0 = std::array{0};
-    public: static constexpr std::array v1 = v0;
-    public: static const myclass3 v2;
+    public: static constexpr auto v1 = v0;// OK: Also uses the Cpp2 placeholder type.
+    public: static const myclass3 v2;// OK: Doesn't use the Cpp2 placeholder type.
     public: static constexpr auto v3 = v0;
-    // v4 :== v2; // Not (yet) supported.
-    // v5: myclass4 == :myclass4 = ();; // Not yet supported.
-    // v6: myclass5 == :myclass5 = ();; // Not yet supported.
-    // v7 :== myclass3(); // Not (yet) supported.
-
-    // There's also a false positive:
-    // <https://github.com/hsutter/cppfront/issues/666#issuecomment-1722329609>.
+    public: static const myclass3 v4;// OK: Doesn't use the Cpp2 placeholder type.
+    public: static const myclass4 v5;// OK: Doesn't use the Cpp2 placeholder type.
+    public: static const myclass5 v6;// OK: Doesn't use the Cpp2 placeholder type.
 };
 
 class myclass4 {};
 
 template<typename T> class myclass6 {
     public: template<typename U> 
 CPP2_REQUIRES_ (true)
-#line 56 "pure2-type-and-namespace-aliases.cpp2"
+#line 52 "pure2-type-and-namespace-aliases.cpp2"
     static constexpr auto v = 0;
 };
 
@@ -118,6 +114,9 @@ auto const& v2 = std::move(v);
 #line 23 "pure2-type-and-namespace-aliases.cpp2"
 }
 
+#line 26 "pure2-type-and-namespace-aliases.cpp2"
+    template <typename T> inline CPP2_CONSTEXPR int myclass2<T>::value = 42;
+
 #line 29 "pure2-type-and-namespace-aliases.cpp2"
 auto main() -> int{
     using view = std::string_view;
@@ -128,6 +127,9 @@ auto main() -> int{
 }
 
 #line 42 "pure2-type-and-namespace-aliases.cpp2"
-    inline CPP2_CONSTEXPR myclass3 myclass3::v2 = myclass3{};
+    inline CPP2_CONSTEXPR myclass3 myclass3::v2 = myclass3();
 
+    inline CPP2_CONSTEXPR myclass3 myclass3::v4 = v2;
+    inline CPP2_CONSTEXPR myclass4 myclass3::v5 = myclass4();
+    inline CPP2_CONSTEXPR myclass5 myclass3::v6 = myclass5();
 

source/cppfront.cpp

@@ -4958,25 +4958,6 @@ class cppfront
     }
 
 
-    auto has_potentially_incomplete_type(
-        declaration_node const& n,
-        type_id_node const& t
-    )
-        -> bool
-    {
-        auto type_id = t.get_token();
-
-        if (!type_id) {
-            return false;
-        }
-
-        if (auto parent = n.get_parent()) {
-            return parent->name() && *type_id == *parent->name();
-        }
-
-        return false;
-    }
-
     //-----------------------------------------------------------------------
     //
     auto emit(
@@ -5098,8 +5079,7 @@ class cppfront
                     && n.is_object_alias()
                 );
                 return !a->type_id
-                       || a->type_id->is_wildcard()
-                       || !has_potentially_incomplete_type(n, *a->type_id);
+                       || a->type_id->is_wildcard();
             };
 
             //  Namespace-scope aliases are emitted in phase 1,