Automatically convert C++ methods taking a completion block to async?

Development C++ interoperability
1

If I have this Objective-C class:

@interface Foo : NSObject
-(void)requestURL:(NSString *)url completion:(void (^)(NSData * _Nullable))completion;
@end

It automatically gets exposed to Swift so I can call it like this:

let foo = Foo()
let data = await foo.requestUrl("https://example.com")

Say I have this C++ class:

class Bar {
  public:
    Bar();
    void requestUrl(NSString *url, void (^completion)(NSData * _Nullable));
} SWIFT_SHARED_REFERENCE(retainFunc, releaseFunc);

Right now in Swift with C++ interop enabled, I have to use the completion block:

let bar = Bar()
bar.requestUrl("https://example.com") { dta in 
  //handle response
}

Is it reasonable to hope that someday Swift’s C++ interop will automatically convert this to async like it does for Objective-C? Or better yet, is there a way to get that to work today?

let bar = Bar()
let data = await bar.requestUrl("https://example.com")

I’m hoping the conversion logic for the Objective-C methods lives in Swift and doesn’t depend on the Objective-C runtime…?

2

More generally, is there any sort of roadmap for enhancements to the C++ interop?

3

You could just extend the c++ type in swift & add a method that uses continuation to make it async

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