d call cpp example

d/util/cpp-d/bar.d

@@ -0,0 +1,7 @@
+// bar.d 
+extern (C++) int foo(int i, int j, int k);
+
+void main()
+{
+    foo(1, 2, 3);
+}

d/util/cpp-d/foo.cpp

@@ -0,0 +1,12 @@
+// foo.cpp 
+#include <iostream>
+using namespace std;
+
+int foo(int i, int j, int k)
+{
+    cout << "i = " << i << endl;
+    cout << "j = " << j << endl;
+    cout << "k = " << k << endl;
+
+    return 7;
+}

d/util/cpp-d/readme.md

@@ -0,0 +1,43 @@
+# dlang 与 cpp 
+
+```cpp
+// foo.cpp
+#include <iostream>
+using namespace std;
+int foo(int i, int j, int k)
+{
+    cout << "i = " << i << endl;
+    cout << "j = " << j << endl;
+    cout << "k = " << k << endl;
+
+    return 7;
+}
+```
+
+```D
+// bar.d
+extern (C++) int foo(int i, int j, int k);
+
+void main()
+{
+    foo(1, 2, 3);
+}
+```
+
+```
+g++ -c foo.cpp 
+ldc2 bar.d foo.o -L-lstdc++
+```
+
+- 在 windows 环境下，这种操作无法连接成功
+
+- 切换成 ubuntu，不管是 dmd编译器，还是ldc2 编译器，都可以链接成功
+
+- 参考资料 https://dlang.org/spec/cpp_interface.html  
+
+- ```
+  sudo apt-get remove --purge  ldc2
+  sudo apt-get install ldc2 
+  ```
+
+