# Syndicate/js

A fourth-generation implementation of Dataspaces and Syndicate for
TypeScript and JavaScript, in both node.js and the browser. The
implementation techniques herein are the subject of a forthcoming
paper.

## Branches

The `main` branch is where active development happens:

    git clone -b main https://git.syndicate-lang.org/syndicate-lang/syndicate-js

An earlier TypeScript+JavaScript implementation from early 2021 (the
primary difference to `main` being a lack of object-capability
support) can be found on the `typescript1` branch:

    git clone -b typescript1 https://git.syndicate-lang.org/syndicate-lang/syndicate-js

Finally, the `babel-based` branch is from 2018, and is an
implementation for JavaScript only. It extends babel with new syntax
and new plugins, (rather than implementing its own error-tolerant
parser, like `typescript1` and `main`):

    git clone -b babel-based https://git.syndicate-lang.org/syndicate-lang/syndicate-js

## Building

*These instructions are for the `main` branch.*

This project uses [`yarn`](https://yarnpkg.com/), not `npm`.

The repository is a monorepo, using
[yarn workspaces](https://classic.yarnpkg.com/en/docs/workspaces/).
[Lerna](https://lerna.js.org/) is used as a thin
[veneer atop yarn workspaces](https://medium.com/@jsilvax/a-workflow-guide-for-lerna-with-yarn-workspaces-60f97481149d),
providing convenient automation for package version management and
publication.

After a checkout, run:

```shell
make bootstrap
```

Alternatively, running:

```shell
yarn install
./node_modules/.bin/lerna exec yarn prepare
```

will download and install all dependencies and then build all the
packages.

## Licence

@syndicate-lang, an implementation of Syndicate for TypeScript and JavaScript.  
Copyright (C) 2016-2021 Tony Garnock-Jones <tonyg@leastfixedpoint.com>

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program.  If not, see <https://www.gnu.org/licenses/>.



<!-- ## Quickstart -->

<!-- ### Option 1. Create a new program/library using Syndicate/js. -->

<!-- Use `npx @syndicate-lang/create DIRECTORY` or `npm init -->
<!-- @syndicate-lang DIRECTORY`: -->

<!--     npm init @syndicate-lang myprogram -->
<!--     cd myprogram -->
<!--     npm i . -->
<!--     npm run build -->
<!--     node lib/index.js -->

<!-- ### Option 2. Add Syndicate/js to an existing program/library. -->

<!-- Install a few packages from the -->
<!-- [@syndicate-lang](https://www.npmjs.com/org/syndicate-lang) scope on -->
<!-- npmjs.com: -->

<!--     npm i --save-dev @syndicate-lang/syntax @babel/preset-env -->
<!--     npm i --save @syndicate-lang/core -->

<!-- Then, add the `@syndicate-lang/syntax/plugin` to your `.babelrc`. Use -->
<!-- `npx syndicate-babel` in place of `npx babel` to compile your code. -->

<!-- ## Creating a new Syndicate/js project -->

<!-- Create a skeletal `package.json`: -->

<!--     { -->
<!--       "main": "lib/index.js", -->
<!--       "scripts": { -->
<!--         "build": "npx syndicate-babel src --out-dir lib", -->
<!--         "clean": "rm -rf lib" -->
<!--       } -->
<!--     } -->

<!-- The entry point will be `lib/index.js`; the corresponding *source* -->
<!-- file will be `src/index.js`. -->

<!-- Two `npm run` scripts are defined: one which compiles Syndicate/js -->
<!-- source files in `src` to plain JavaScript in `lib`. The compiler uses -->
<!-- Babel; we will configure Babel next. -->

<!-- Create a `.babelrc` file: -->

<!--     { -->
<!--       "presets": [ "@babel/preset-env" ], -->
<!--       "plugins": [ "@syndicate-lang/syntax/plugin" ] -->
<!--     } -->

<!-- Now, install the necessary dependencies. Babel and the Syndicate/js -->
<!-- extensions are needed at build-time: -->

<!--     npm i --save-dev @syndicate-lang/syntax @babel/preset-env -->

<!-- The Syndicate/js runtime and as many drivers as you would like to use -->
<!-- are needed at run-time: -->

<!--     npm i --save @syndicate-lang/core -->
<!--     npm i --save @syndicate-lang/driver-timer -->

<!-- Finally, create the main program file. Create a directory `src`, and -->
<!-- then a file `src/index.js`: -->

<!-- ```javascript -->
<!-- const { LaterThan } = activate require("@syndicate-lang/driver-timer"); -->

<!-- spawn named 'ticker' { -->
<!--   field this.counter = 0; -->
<!--   field this.deadline = +(new Date()) / 1000.0; -->

<!--   on start { console.log('ticker starting'); } -->
<!--   on stop  { console.log('ticker stopping'); } -->

<!--   on asserted LaterThan(this.deadline) { -->
<!--     this.counter++; -->
<!--     console.log('tick', new Date(), this.counter); -->
<!--     this.deadline += 1; -->
<!--   } -->

<!--   stop on (this.counter == 5); -->
<!-- } -->
<!-- ``` -->

<!-- Now, compile the project: -->

<!--     npm run build -->

<!-- Finally, run the program: -->

<!--     node lib/index.js -->

<!-- The output should be something like: -->

<!--     ticker starting -->
<!--     tick 2018-11-05T14:23:27.713Z 1 -->
<!--     tick 2018-11-05T14:23:28.705Z 2 -->
<!--     tick 2018-11-05T14:23:29.706Z 3 -->
<!--     tick 2018-11-05T14:23:30.706Z 4 -->
<!--     tick 2018-11-05T14:23:31.707Z 5 -->
<!--     ticker stopping -->