# How to use swift standard library types in cpp package?

**URL:** <https://forums.swift.org/t/how-to-use-swift-standard-library-types-in-cpp-package/69048>\
**Category:** Using Swift\
**Tags:** cxx-interop\
**Created:** [December 18, 2023, 5:40pm UTC](https://forums.swift.org/t/how-to-use-swift-standard-library-types-in-cpp-package/69048 "2023-12-18T17:40:52Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![masters3d](https://avatars.discourse-cdn.com/v4/letter/m/c4cdca/32.png) [@masters3d](https://forums.swift.org/u/masters3d)\
**Post date:** [December 18, 2023, 5:40pm UTC](https://forums.swift.org/t/how-to-use-swift-standard-library-types-in-cpp-package/69048/1 "2023-12-18T17:40:53Z")

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Over the weekend I was trying to send some data from swift side to cpp side.  
How do I import the following headers? Perhaps those are just arbitrary headers from the documentation, it was not clear to me.

```swift
#include <SwiftLibrary-Swift.h> // fatal error: 'SwiftLibrary-Swift.h' file not found
#include <StringsAndNumbers-Swift.h> // fatal error: 'StringsAndNumbers-Swift.h' file not found

```

I also tried #include \<swift/bridging\> and its not able to find swift:: module. Thoughts?

> **[Swift.org](https://www.swift.org/documentation/cxx-interop/#list-of-customization-macros-in-swiftbridging)**
>
> Swift is a general-purpose programming language built using a modern approach to safety, performance, and software design patterns.

```swift
#include <swift/bridging>

struct KeyGrid {

  std::vector<std::vector<Key*>> data;

  KeyGrid(swift::Array<Key*> input) //: error: use of undeclared identifier 'swift'
  {   
  //....
  };

```

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<div class="post-metadata">

**Author:** ![abhishekj](https://sea2.discourse-cdn.com/swift/user_avatar/forums.swift.org/abhishekj/32/37291_2.png) [@abhishekj](https://forums.swift.org/u/abhishekj)\
**Post date:** [November 6, 2024, 7:02am UTC](https://forums.swift.org/t/how-to-use-swift-standard-library-types-in-cpp-package/69048/2 "2024-11-06T07:02:07Z")

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Did you find an answer for this? I am also getting an error: " No member named 'String' in namespace 'swift'"