[Kernel] Add syntax for unevaluated constants

Add Kernel syntactic support for constants constructed by
bool.fromEnvironment, int.fromEnvironment, and String.fromEnvironment.
These values are not necessarily available at compile time.  Because
constants can depend on these values, there is also an unevaluated constant
that represents an expression depending on environment values.

This syntax is not yet produced by the Fasta compiler.

Change-Id: Ie96ea7f60a7efcd35ac802b320a00f398d41232e
Reviewed-on: https://dart-review.googlesource.com/c/88827
Commit-Queue: Kevin Millikin <kmillikin@google.com>
Reviewed-by: Aske Simon Christensen <askesc@google.com>
13 files changed
tree: e07fca3403814ff0e65e15e5c85e8f4c71a3c817
  1. .github/
  2. build/
  3. client/
  4. docs/
  5. pkg/
  6. runtime/
  7. samples/
  8. samples-dev/
  9. sdk/
  10. tests/
  11. third_party/
  12. tools/
  13. utils/
  14. .clang-format
  15. .gitattributes
  16. .gitconfig
  17. .gitignore
  18. .gn
  19. .mailmap
  20. .packages
  21. .vpython
  22. AUTHORS
  23. BUILD.gn
  24. CHANGELOG.md
  25. codereview.settings
  26. CONTRIBUTING.md
  27. dartdoc_options.yaml
  28. DEPS
  29. LICENSE
  30. PATENTS
  31. PRESUBMIT.py
  32. README.dart-sdk
  33. README.md
  34. WATCHLISTS
README.md

Dart

Dart is an open-source, scalable programming language, with robust libraries and runtimes, for building web, server, and mobile apps.

Using Dart

Visit the dartlang.org to learn more about the language, tools, getting started, and more.

Browse pub.dartlang.org for more packages and libraries contributed by the community and the Dart team.

Building Dart

If you want to build Dart yourself, here is a guide to getting the source, preparing your machine to build the SDK, and building.

There are more documents on our wiki.

Contributing to Dart

The easiest way to contribute to Dart is to file issues.

You can also contribute patches, as described in Contributing.

License & patents

See LICENSE and PATENTS.