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[cxx-interop] Add documentation about inferring SWIFT_SHARED_REFERENCE in c++ inheritance #1078

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[cxx-interop] Add documentation about inferring SWIFT_SHARED_REFERENCE in c++ inheritance #1078

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[cxx-interop] Add documentation about inferring SWIFT_SHARED_REFERENC…
fahadnayyar Jun 10, 2025
5115e68
Removed Swift class types from the text
fahadnayyar Jul 1, 2025
dd4d780
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fahadnayyar Jul 4, 2025
66da0bf
added some more info
fahadnayyar Jul 4, 2025
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5 changes: 5 additions & 0 deletions documentation/cxx-interop/index.md
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Expand Up @@ -1255,6 +1255,11 @@ object.doSomething()
// `object` will be released here.
```

### Inference of Shared Reference behaviour in Derived Types
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@fahadnayyar fahadnayyar Jul 7, 2025

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TODO: ### -> ####


When a C++ type inherits from a `SWIFT_SHARED_REFERENCE` base type, the Swift compiler automatically infers `SWIFT_SHARED_REFERENCE` annotation for the derived type.
The derived type also gets imported as a reference type, and uses the same `retain` and `release` functions as its base class.

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@fahadnayyar fahadnayyar Jul 4, 2025

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@j-hui I changed some text based on your suggestions but added my flavor as well. How does it look now?

### Inheritance and Virtual Member Functions

Similar to value types, casting an instance of a derived reference type to a
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