Add Expression

[nicklockwood]

Pull Request Description

Replace with a description of this pull request. Instructions for adding
projects are available in the README.

Acceptance Criteria

To be accepted into the Swift source compatibility test suite, a project must:

• be an Xcode or swift package manager project
• support building on either Linux or macOS
• target Linux, macOS, or iOS/tvOS/watchOS device
• be contained in a publicly accessible git repository
• maintain a project branch that builds against Swift 4.0 and passes any unit tests
• have maintainers who will commit to resolve issues in a timely manner
• be compatible with the latest GM/Beta versions of Xcode and swiftpm
• add value not already included in the suite
• be licensed with one of the following permissive licenses:
  • BSD
  • MIT
  • Apache License, version 2.0
  • Eclipse Public License
  • Mozilla Public License (MPL) 1.1
  • MPL 2.0
  • CDDL
• pass ./project_precommit_check script run

Ensure project meets all listed requirements before submitting a pull request.

[nicklockwood]

@swift-ci Please test source compatibility

[shahmishal]

@swift-ci test

[shahmishal]

fatal: reference is not a tree: d8bb2bc535e2895b5fbe66f4872327b654d19a34

cc: @nicklockwood

[justice-adams-apple]

Hi @nicklockwood 👋 , It appears the commit you specified in this PR is actually from another project (https://github.com/line/line-sdk-ios-swift.git).

I suspect this was a copy and paste error while setting up the projects.json element.