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While the precedence outlined by the table should only be used as a
guideline, users are instead finding third-party sources when googling
which do not highlight potential issues and are not able to
identify/search that this table still approximates the behavior even if
they navigate to the language tour.

This PR makes the table more searchable and identifiable as outlining
the approximate precedence, while also clarifying the warning which was
a bit confusing, focusing on that it can just be used as a "helpful
guide". Beyond that, this adds the associativity labels present on the
language spec's "helpful guide".

Fixes #4287


Co-authored-by: Anthony Sansone <>

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Dart The Dart language site (

Build Status SVG OpenSSF Scorecard SVG first-timers SVG

The site, built with Jekyll and hosted on Firebase.

We welcome contributions, and we're first-timer friendly!

Getting started

Start by looking for an issue that catches your interest, or create an issue with your proposed change. Ask for the issue to be assigned to you.

To update this site, fork the repo, make your changes, and generate a pull request. For simple changes (such as to CSS and text), you probably don't need to build this site. Often you can make changes using the GitHub UI.

NOTE: If you clone this repo locally, see the instructions below on cloning with its submodule.

If your change involves code samples, adds/removes pages, or affects navigation, you'll need to build and test your work before submitting.

If you want or need to build, follow the steps below.

Help us improve these instructions! If you have any problems getting set up to build or performing the actual build, please edit this README or file an issue (or both).

Before you build this site

For changes beyond simple text and CSS tweaks, we recommend building the site.

1. Get the prerequisites

Install the following tools, if you don't have them already:

  • bash, the Bourne shell. These instructions assume you're using bash, and setup might not work if you use another shell.

  • GNU Make. On Windows the easiest way to install Make is choco install make using command prompt or powershell as an admin. Other options include using a subsystem.

  • Docker. We use Docker for local dev, tests, and building the site. Install it from

  • Firebase CLI, for hosting the site locally. One way to get this is to run npm install -g firebase-tools. For full setup details, read the Firebase CLI documentation.

2. Clone this repo and its submodules

Note: This repo has git submodules, which affects how you clone it. The GitHub documentation has general help on forking and cloning repos.

If you're not a member of the Dart organization, we recommend you create a fork of this repo under your own account, and then submit a PR from that fork.

Once you have a fork (or you're a Dart org member), choose one of the following submodule-cloning techniques:

  • Clone the repo and its submodule at the same time using the --recurse-submodules option:

    $ git clone --recurse-submodules


  • If you've already cloned the repo without its submodule, then run this command from the repo root:

    $ git submodule update --init --recursive

Note: At any time during development you can use the git submodule command to refresh submodules:

$ git pull; git submodule update --init --recursive

Setting up your local environment and serve changes

  1. Optional: After cloning the repo and its submodules, create a branch for your changes:

    $ git checkout -b <BRANCH_NAME>
  2. If the Docker Desktop application isn't already running on your machine, start it. Look for the Docker status icon: if it has an exclamation point (!), then update Docker Desktop before proceeding.

  3. Run the initial local setup command:

    $ make setup
  4. Serve the site locally (via docker-compose):

    $ make up

    The site is generated, and then the development server runs in the Docker container, with the generated _site directory visible locally as a mirrored volume from inside the container.

  5. View your changes in the browser by navigating to http://localhost:4000.

    Note: Unless you're editing files under site-shared, you can safely ignore ERROR: directory is already being watched messages. For details, see #1363.

  6. Make your changes to the local repo.

    The site will rebuild and the browser will autoreload to reflect the changes.

    Tip: If you aren't seeing the changes you expect (e.g. src/_data), ctrl-C out of your running dev server and rebuild the site from scratch using the following commands:

    $ make down && make clean && make up
  7. Commit your changes to the branch and submit your PR.

    See Pre-push site checks

  8. When you've finished developing, shut down the Docker container:

    $ make down

Tip: To find additional commands, read the Makefile. For example, if you need to debug the Docker setup, you can run:

$ make run

Pre-push site checks

Checking documentation and example code

If you've made changes to this site's documentation and/or example code, and committed locally, then run the following command before pushing your work:

# Enter a running Docker container shell
make run

# Check/validate example code

# Check links for 404 errors

If these scripts report errors or warnings, then address those issues and rerun the above commands. Otherwise, you can push your changes.

Deploying to a staging site

You can deploy your local edits to a personal Firebase hosting staging site as follows:

  1. If you don't already have a Firebase project,

    • Navigate to the Firebase Console and create your own Firebase project (for example, dart-dev-staging).

    • Head back to your local repo shell and verify that you are logged in.

      $ firebase login
    • Ensure that your project exists and activate that project:

      $ firebase projects:list
      $ firebase use <your-project>
  2. Build the site via Docker:

    $ make build

    This will build the site and copy it to your local _site directory. If that directory previously existed, it will be replaced.

  3. Deploy to your activated Firebase project's default hosting site:

    $ FIREBASE_PROJECT=<your-project> make deploy

    TIP: Add your FIREBASE_PROJECT env var to your .env file and it will overwrite the default every time you deploy without specifying.

  4. Navigate to your PR on GitHub and update it with the location of the staged version, the names of your reviewers, and so on.

Creating and/or editing DartPad example code

Most of the code used to create DartPad examples is hosted on GitHub. However, this repo also contains some *.dart files responsible for DartPad example code.

Refresh DartPad HTML tooltips

Files that require DartPad HTML to be manually updated include instructions at the top that specify running:

$ tool/create_code_with_tooltips.dart

Follow the instructions in those files to refresh the appropriate code.

DartPad picker

The DartPad example picker must be manually compiled if changes are made. This will regenerate the associated JavaScript file in src/assets/dash/js:

$ tool/

Dockerfile Maintenance

Dart SDK and Node PPA Checksum values

Since both the Dart SDK and Node PPA curl remote files, it's important to verify checksum values. Both installs use latest and lts respectively, so these files may be periodically updated. When this happens, local checksums may fail and This will break the Docker/Compose setup/build. You will see the relevant output in your shell e.g. DART CHECKSUM FAILED!.... When this happens, run the following command:

make run

make fetch-sums

This command will output the updated checksum values for both Node and Dart, and that output will be formatted similar or the same as what is currently in the Dockerfile. Copy this output and replace the relevant install code in the Dockerfile, then rerun your setup/build again.