What is export * in module.modulemap file inside each framework?

Question

I have created one framework named Communication, inside framework container there is one module.modulemap file.

module.modulemap<

Answer 1

[History]

Modular Framework contains .modulemap file in the next path

module_name.framework/Modules/module_name.modulemap

As for Naming my rule is

ProductName -> Product Module Name -> <name>.modulemap -> framework module <name>

When you create a library you should create and setup it manually[Custom modulemap], when you create a framework Xcode generates its automatically if Build Settings -> Defines Module -> YES.

When you create your own .modulemap file you have to update a path in Build Settings -> Module Map File

Lets take a look at the example:
Note: I use explicit module to show that Xcode will generate errors

//ClassA.h
#import "ClassAA.h"

//ClassB.h
//ClassAA.h

//Module.h
#import "ClassA.h"
#import "ClassB.h"

//Module.modulemap
framework module Module {
    //Expose all imports from Module.h for Module module recursively
    //    import Module - you can use ClassA, ClassB, ClassAA
    umbrella header "Module.h" 
    
    //explicit module * { }
    //    1. `module` works only with `umbrella`
    //    2. Generates a submodule for every header inside Module.h recursively
    //        import Module.ClassA, import Module.ClassB, import Module.ClassC
    //explicit module * { export * }
    //export all imports from <submodule_name>.h for <submodule_name> module
    //    import Module.ClassA - you can use ClassA, ClassAA (ClassAA was added)
    explicit module * { export * }

    //export all imports from Module.h for Module module
    //    import Module.ClassA - you can use ClassA, ClassAA, ClassB(ClassB was added)
    export *
}