在Cocoa项目中使用C ++类时，找不到标准的C ++包含

I have a Cocoa project (a Mac OS X app), all Objective-C. I pulled in one C++ class (which I know works) from another project, and make an Objective-C wrapper for it. The ObjC wrapper class is using a .mm extension. However, the C++ header file contains I have a Cocoa project (a Mac OS X app), all Ob